WO2019093598A1 - Apparatus and method for encoding motion information, and decoding apparatus and method - Google Patents

Abstract

Disclosed is a method for decoding motion information, according to one embodiment, comprising the steps of: identifying a type of omitted motion information not included in a bitstream among a plurality of pieces of motion information to be used in the decoding of an inter-predicted current block; acquiring the omitted motion information on the basis of a predetermined scheme; and decoding the current block on the basis of the plurality of pieces of motion information including the acquired omitted motion information.

Description

Apparatus and method for encoding motion information, and apparatus and method for decoding motion information

This disclosure relates to the field of video encoding and decoding. More particularly, this disclosure relates to a method and apparatus for encoding motion information of video, and a method and apparatus for decoding.

In the video coding and decoding method, one picture may be divided into macroblocks for encoding an image, and each macroblock may be predictively encoded through inter prediction or intraprediction.

Inter prediction is a method of compressing an image by eliminating temporal redundancy between pictures, and is a typical example of motion estimation encoding. Motion estimation coding predicts blocks of a current picture using at least one reference picture. A reference block most similar to the current block can be searched in a predetermined search range by using a predetermined evaluation function.

The current block is predicted based on the reference block, and the residual block generated and predicted is subtracted from the current block. At this time, in order to more accurately perform the prediction, interpolation is performed on the search range of the reference picture to generate pixels of a sub pel unit smaller than an integer pel unit, Lt; RTI ID = 0.0 > inter-prediction. ≪ / RTI >

In a codec such as H.264 AVC (Advanced Video Coding) and HEVC (High Efficiency Video Coding), in order to predict a motion vector of a current block, previously coded blocks adjacent to the current block or blocks The motion vector of the current block is used as a prediction motion vector of the current block.

According to an embodiment of the present invention, there is provided a method of decoding motion information, the method comprising: identifying a type of skip motion information not included in a bitstream among a plurality of motion information used for decoding an inter-predicted current block; Obtaining the skip motion information based on a predetermined scheme; And decoding the current block based on a plurality of pieces of motion information including the obtained skip motion information.

The apparatus and method for encoding motion information and the apparatus and method for decoding motion information according to an embodiment of the present invention can reduce a bit amount by omitting some of motion information required for decoding an inter- have.

BRIEF DESCRIPTION OF THE DRAWINGS A brief description of each drawing is provided to more fully understand the drawings recited herein.

1 shows a block diagram of an image decoding apparatus capable of decoding an image based on at least one of block type information and division type information according to an embodiment.

2 is a block diagram of an image encoding apparatus capable of encoding an image based on at least one of block type information and division type information according to an embodiment.

FIG. 3 illustrates a process in which at least one encoding unit is determined by dividing a current encoding unit according to an embodiment.

FIG. 4 illustrates a process in which at least one encoding unit is determined by dividing an encoding unit in the form of a non-square according to an embodiment.

FIG. 5 illustrates a process in which an encoding unit is divided based on at least one of block type information and division type information according to an embodiment.

FIG. 6 illustrates a method of determining a predetermined encoding unit among odd number of encoding units according to an embodiment.

FIG. 7 illustrates a sequence in which a plurality of encoding units are processed when a current encoding unit is divided to determine a plurality of encoding units according to an embodiment.

FIG. 8 illustrates a process in which, if an encoding unit can not be processed in a predetermined order according to an embodiment, it is determined that the current encoding unit is divided into odd number of encoding units.

FIG. 9 illustrates a process in which a first encoding unit is divided according to an embodiment to determine at least one encoding unit.

10 illustrates that when a non-square type second coding unit determined by dividing a first coding unit according to an embodiment satisfies a predetermined condition, a form in which the second coding unit can be divided is limited .

FIG. 11 illustrates a process in which a square-shaped encoding unit is divided when division type information can not be divided into four square-shaped encoding units according to an embodiment

FIG. 12 illustrates that the processing order among a plurality of coding units may be changed according to a division process of a coding unit according to an exemplary embodiment.

FIG. 13 illustrates a process of determining the depth of an encoding unit according to a change in type and size of an encoding unit when a plurality of encoding units are determined by recursively dividing an encoding unit according to an embodiment.

FIG. 14 illustrates a depth index (hereinafter referred to as PID) for coding unit classification and depth that can be determined according to the type and size of coding units according to an exemplary embodiment.

FIG. 15 illustrates that a plurality of coding units are determined according to a plurality of predetermined data units included in a picture according to an embodiment.

FIG. 16 shows a processing block serving as a reference for determining a determination order of a reference encoding unit included in a picture according to an embodiment.

FIG. 17 shows coding units that can be determined for each picture when combinations of types in which coding units can be divided according to an embodiment are different from picture to picture.

18 illustrates various types of coding units that can be determined based on the division type information that can be represented by a binary code according to an embodiment.

Figure 19 shows another form of an encoding unit that can be determined based on partition type information that can be represented in binary code according to one embodiment.

20 is a block diagram of an image encoding and decoding system performing loop filtering.

FIG. 21 is a diagram illustrating an example of filtering units included in the maximum encoding unit according to an exemplary embodiment, and filtering performing information of the filtering unit.

FIG. 22 illustrates a process of performing merge or split between coding units determined according to a predetermined coding method according to an embodiment.

FIG. 23 shows an index according to a Z scan sequence of an encoding unit according to an embodiment.

24 is a diagram illustrating reference samples for intraprediction of an encoding unit according to an embodiment.

25 is a block diagram illustrating a configuration of a motion information decoding apparatus according to an embodiment.

26 is a flowchart for explaining a motion information decoding method according to an embodiment.

27 is a block diagram illustrating a configuration of a motion information encoding apparatus according to an embodiment.

28 is a flowchart for explaining a motion information encoding method according to an embodiment.

29 and 30 are diagrams for explaining motion information used for decoding an inter-predicted block.

31 and 32 are exemplary diagrams showing omission motion information corresponding to the motion information omission mode.

33 is a diagram illustrating candidate blocks used to obtain skip motion information according to an embodiment.

FIG. 34 shows an exemplary syntax for acquiring skipped motion information according to a motion information skip mode for a bidirectionally predicted block.

35 shows an exemplary syntax for obtaining information indicating the MVR of the current block.

36 shows a case where a minimum MVR selectable for a current block is a quarter-pixel unit MVR, a motion vector corresponding to a 1/4 pixel unit MVR, a 1/2 pixel unit MVR, a 1 pixel unit MVR, and a 2 pixel unit MVR And the positions of the pixels that can be pointed to.

37 and 38 are diagrams for explaining a method of adjusting a predicted motion vector or a residual motion vector.

According to an embodiment of the present invention, there is provided a method of decoding motion information, the method comprising: identifying a type of skip motion information not included in a bitstream among a plurality of motion information used for decoding an inter-predicted current block; Obtaining the skip motion information based on a predetermined scheme; And decoding the current block based on a plurality of pieces of motion information including the obtained skip motion information.

The skip motion information may include information on a plurality of candidate blocks spatially or temporally related to the current block by checking whether or not the motion information exists according to the priority, . ≪ / RTI >

The skip motion information may be obtained by combining motion information of a plurality of candidate blocks having motion information among a plurality of candidate blocks spatially or temporally related to the current block.

The skip motion information may be obtained based on predetermined basic motion information.

The skip motion information may be obtained based on motion information derived through DMVD (decoder side MV derivation).

The step of acquiring the skip motion information may include acquiring a plurality of skip motion information based on different schemes if the number of skip motion information is plural.

The type of the skip motion information may be at least one of information indicating a motion vector resolution of the current block, a prediction direction of the current block, information on the current block, information on a previously decoded neighboring block, Can be identified based on one.

The method of decoding motion information may further include acquiring information indicating whether or not motion information skip processing is applied, and when the application of the motion information skip processing is confirmed, the skip motion information may be identified.

The information indicating whether or not the motion information skip process is applied includes information on a motion vector resolution of the current block, a prediction direction of the current block, information on the current block, information on previously decoded neighboring blocks, And a flag indicating whether processing is applied or not.

The method of decoding motion information according to claim 1, further comprising the step of acquiring information indicating a skip mode of motion information when the current block is bi-directionally predicted, wherein the skip mode of the motion information comprises: A first mode in which a residual motion vector is identified as the skip motion information, and a second mode in which a residual motion vector corresponding to the second reference image list is identified as the skip motion information.

Wherein the plurality of motion information includes information indicating a motion vector resolution of a current block and information indicating a predictive motion vector, and the decoding method of the motion information includes adjusting the predictive motion vector according to the motion vector resolution of the current block The method comprising the steps of:

The decoding method of the motion information may further include acquiring motion information other than the skip motion information from the bitstream, among the plurality of motion information.

According to an embodiment of the present invention, there is provided a method of decoding motion information, comprising: obtaining information indicating a bidirectional prediction type for a current block predicted in both directions; And a second residual motion vector corresponding to a first reference motion vector corresponding to a first reference motion vector list and a second reference motion vector corresponding to a second reference motion vector among a plurality of motion information associated with the current block, And decoding the current block using at least one motion information.

The motion information decoding apparatus includes an identification unit for identifying a type of omission motion information not included in a bitstream among a plurality of motion information used for decoding an inter-predicted current block; And a decoding unit that obtains the skip motion information based on a predetermined method and decodes the current block based on a plurality of pieces of motion information including the obtained skip motion information.

According to an embodiment of the present invention, there is provided a method of encoding motion information, comprising: determining a type of skip motion information to be skipped from a bitstream, among a plurality of motion information used for decoding an inter-predicted current block; Obtaining the skip motion information based on a predetermined scheme; And generating a bitstream including motion information other than the skip motion information among the plurality of motion information.

The present disclosure is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail with reference to the drawings. It should be understood, however, that it is not intended to be limited to the embodiments of this disclosure, and that this disclosure includes all modifications, equivalents, and alternatives falling within the spirit and scope of the various embodiments.

In the following description of the embodiments, a detailed description of related arts will be omitted if it is determined that the gist of the present disclosure may be unnecessarily obscured. In addition, numerals (e.g., first, second, etc.) used in the description of the specification are merely an identifier for distinguishing one component from another.

Also, in this specification, when an element is referred to as being " connected " or " connected " with another element, the element may be directly connected or directly connected to the other element, It should be understood that, unless an opposite description is present, it may be connected or connected via another element in the middle.

In the present specification, a component represented by 'unit', 'module', or the like refers to a case where two or more components are combined into one component, or one component is divided into two or more ≪ / RTI > In addition, each of the components to be described below may additionally perform some or all of the functions of the other components in addition to the main functions of the component itself, and some of the main functions And may be performed entirely by components.

Also, in this specification, an 'image' or a 'picture' may be a still image of a video or a moving image, that is, a video itself.

In this specification, 'sample' means data to be processed as data assigned to a sampling position of an image. For example, pixel values in the image of the spatial domain, and transform coefficients on the transform domain may be samples. A unit including at least one of these samples may be defined as a block.

In the present specification, the 'current block' may mean a block of a maximum encoding unit, an encoding unit, a prediction unit, or a conversion unit of a current image to be encoded or decoded.

In this specification, 'motion vector resolution' may refer to the precision of the position of a pixel that a motion vector determined through inter-prediction among pixels included in a reference image (or an interpolated reference image) can point to . The fact that the motion vector resolution has N pixels units (N is a rational number) means that the motion vector can have an accuracy of N pixels units. As an example, the motion vector resolution in the unit of a quarter pixel may mean that the motion vector can point to a pixel position in a quarter pixel unit (i.e., a sub-pixel unit) in the interpolated reference image, May mean that a motion vector may indicate a pixel position corresponding to one pixel unit (i.e., an integer pixel unit) in the interpolated reference picture.

Herein, 'candidate motion vector resolution' means at least one motion vector resolution that can be selected as a motion vector resolution of a block, 'candidate block' is mapped to a candidate motion vector resolution, and prediction Means one or more blocks that can be used as a block for a motion vector.

Also, in this specification, 'pixel unit' may be replaced with terms such as pixel accuracy, pixel accuracy, and the like.

Hereinafter, with reference to FIG. 1 to FIG. 24, an image encoding method and apparatus, an image decoding method, and an apparatus thereof based on an encoding unit and a conversion unit of a tree structure according to an embodiment are disclosed. Each of the image encoding apparatus 200 and the image decoding apparatus 100 to be described with reference to FIGS. 1 to 24 includes a motion information encoding apparatus 2700 and a motion information decoding apparatus 2500, which will be described with reference to FIGS. 25 to 38, Respectively.

FIG. 1 shows a block diagram of an image decoding apparatus 100 capable of decoding an image based on at least one of block type information and division type information according to an embodiment.

1, the video decoding apparatus 100 includes a bitstream obtaining unit 110 for obtaining predetermined information such as partition type information and block type information from a bitstream according to an embodiment, And a decoding unit 120 for decoding the image. In a case where at least one of the block type information and the division type information is obtained in the bitstream obtaining unit 110 of the video decoding apparatus 100 according to an embodiment, the decoding unit 120 of the video decoding apparatus 100 may block At least one encoding unit for dividing an image based on at least one of information and division type information can be determined.

According to one embodiment, the decoding unit 120 of the image decoding apparatus 100 may determine the type of the encoding unit based on the block type information. For example, the block type information may include information indicating whether the encoding unit is a square or a non-square. The decoding unit 120 may determine the type of the encoding unit using the block type information.

According to one embodiment, the decoding unit 120 may determine what type of encoding unit is to be divided based on the division type information. For example, the division type information may indicate information on the type of at least one encoding unit included in the encoding unit.

According to one embodiment, the decoding unit 120 may determine whether the encoding unit is divided or not according to the division type information. The division type information may include information on at least one encoding unit included in the encoding unit. If the division type information indicates that only one encoding unit is included in the encoding unit, or indicates that the encoding unit is not divided, The decoding unit 120 may determine that the encoding unit including the division type information is not divided. When the division type information indicates that the coding unit is divided into a plurality of coding units, the decoding unit 120 may divide the coding unit into a plurality of coding units included in the coding unit based on the division type information.

According to one embodiment, the division type information indicates whether to divide an encoding unit into a plurality of encoding units or can indicate which direction to divide. For example, the division type information may indicate that division is performed in at least one of a vertical direction and a horizontal direction, or may indicate that division is not performed.

FIG. 3 illustrates a process in which the image decoding apparatus 100 determines at least one encoding unit by dividing a current encoding unit according to an embodiment.

The block shape may include 4Nx4N, 4Nx2N, 2Nx4N, 4NxN, or Nx4N. Where N may be a positive integer. The block type information is information indicating at least one of a ratio, or a size, of a shape, direction, width, and height of an encoding unit.

The shape of the encoding unit may include a square and a non-square. If the width and height of the encoding unit are the same (4Nx4N), the image decoding apparatus 100 can determine the block type information of the encoding unit as a square. The image decoding apparatus 100 can determine the shape of the encoding unit as a non-square.

The image decoding apparatus 100 can determine the block type information of the encoding unit as a non-square when the lengths of the widths and heights of the encoding units are different (4Nx2N, 2Nx4N, 4NxN, or Nx4N). When the shape of the coding unit is a non-square shape, the image decoding apparatus 100 sets the width and height ratio of the block type information of the coding unit to 1: 2, 2: 1, 1: 4, 4: Or 8: 1. Further, based on the length of the width of the coding unit and the length of the height, the video decoding apparatus 100 can determine whether the coding unit is the horizontal direction or the vertical direction. Further, the image decoding apparatus 100 can determine the size of the encoding unit based on at least one of the width of the encoding unit, the length of the height, and the width.

According to an exemplary embodiment, the image decoding apparatus 100 may determine the type of the encoding unit using the block type information and determine the type of the encoding unit to be divided using information on the division type mode. That is, according to which block type the block type information used by the video decoding apparatus 100 indicates, the division method of the encoding unit indicated by the information on the split mode mode can be determined.

The image decoding apparatus 100 may obtain information on the split mode mode from the bit stream. However, the present invention is not limited thereto, and the image decoding apparatus 100 and the image encoding apparatus 200 may acquire information on the promised split mode mode based on the block type information. The image decoding apparatus 100 may acquire information on the promised divided mode mode for the maximum encoding unit or the minimum encoding unit. For example, the image decoding apparatus 100 can determine the size of the maximum encoding unit to be 256x256. The image decoding apparatus 100 may determine the information about the promised division mode in advance as a quad split. Quad partitioning is a split mode mode that bisects both the width and the height of the encoding unit. The image decoding apparatus 100 can obtain a 128x128 encoding unit from the 256x256 maximum encoding unit based on the information on the split mode mode. Also, the image decoding apparatus 100 can determine the size of the minimum encoding unit to be 4x4. The image decoding apparatus 100 can acquire information on the split mode mode indicating " not split " for the minimum encoding unit.

According to one embodiment, the image decoding apparatus 100 may use block type information indicating that the current encoding unit is a square type. For example, the image decoding apparatus 100 can determine whether to divide a square encoding unit according to information on the division mode, vertically or horizontally, or four encoding units. 3, if the block type information of the current encoding unit 300 indicates a square shape, the decoding unit 120 decodes the current encoding unit 300 and the current encoding unit 300 according to the information on the split mode mode, It is possible not to divide the coding unit 310a having the same size or to determine the divided coding units 310b, 310c and 310d based on the information on the division mode mode indicating the predetermined division method.

Referring to FIG. 3, the image decoding apparatus 100 includes two encoding units 310b, 320b, 320c, 320c, 320c, 320c, 320c, Can be determined. The image decoding apparatus 100 may determine two encoding units 310c in which the current encoding unit 300 is divided in the horizontal direction based on the information on the split mode mode indicating that the image is divided in the horizontal direction. The image decoding apparatus 100 can determine four encoding units 310d in which the current encoding unit 300 is divided into the vertical direction and the horizontal direction based on the information on the split mode mode indicating that the image is divided into the vertical direction and the horizontal direction have. However, the division type in which the square encoding unit can be divided should not be limited to the above-mentioned form, but may include various forms in which the information on the division type mode can be represented. The predetermined divisional form in which the square encoding unit is divided will be described in detail by way of various embodiments below.

FIG. 4 illustrates a process in which the image decoding apparatus 100 determines at least one encoding unit by dividing a non-square encoding unit according to an embodiment.

According to an embodiment, the image decoding apparatus 100 may use block type information indicating that the current encoding unit is a non-square format. The video decoding apparatus 100 may determine whether to divide the non-square current encoding unit according to the information on the split mode mode or not in a predetermined method. 4, when the block type information of the current encoding unit 400 or 450 indicates a non-square shape, the image decoding apparatus 100 performs a current encoding process according to the information on the split mode mode, The encoding unit 410 or 460 having the same size as the unit 400 or 450 is determined or the encoding unit 420a, 420b, 430a, or 430b divided based on the information on the division mode mode indicating the predetermined division method , 430c, 470a, 470b, 480a, 480b, 480c. The predetermined division method in which the non-square coding unit is divided will be described in detail through various embodiments.

According to an exemplary embodiment, the image decoding apparatus 100 may determine a type in which a coding unit is divided using information on a division type mode. In this case, information on the division type mode may include at least one Lt; / RTI > can be represented by the number of encoding units. Referring to FIG. 4, when the information on the split mode mode indicates that the current encoding unit 400 or 450 is divided into two encoding units, the image decoding apparatus 100 performs a current encoding The unit 400 or 450 may be divided to determine two encoding units 420a, 420b, or 470a and 470b included in the current encoding unit.

When the image decoding apparatus 100 divides the current encoding unit 400 or 450 in the form of a non-square based on the information on the split mode mode, the image decoding apparatus 100 may divide the non- The current encoding unit can be divided in consideration of the position of the long side of the current encoding unit (400 or 450). For example, the image decoding apparatus 100 divides the current encoding unit 400 or 450 in the direction of dividing the long side of the current encoding unit 400 or 450 in consideration of the shape of the current encoding unit 400 or 450 So that a plurality of encoding units can be determined.

According to one embodiment, when the information on the split mode mode indicates that an encoding unit is divided into an odd number of blocks (tri-split), the video decoding apparatus 100 includes the current encoding unit 400 or 450 An odd number of encoding units can be determined. For example, when the information on the split mode mode indicates that the current encoding unit 400 or 450 is divided into three encoding units, the video decoding apparatus 100 encodes the current encoding unit 400 or 450 into three encodings Can be divided into units 430a, 430b, 430c, 480a, 480b, and 480c.

According to one embodiment, the ratio of the width and height of the current encoding unit 400 or 450 may be 4: 1 or 1: 4. If the ratio of width to height is 4: 1, the length of the width is longer than the length of the height, so the block type information may be horizontal. If the ratio of width to height is 1: 4, the block type information may be vertical because the length of the width is shorter than the length of the height. The image decoding apparatus 100 may determine to divide the current encoding unit into odd number blocks based on the information on the split mode mode. The image decoding apparatus 100 can determine the division direction of the current encoding unit 400 or 450 based on the block type information of the current encoding unit 400 or 450. [ For example, when the current encoding unit 400 is the vertical direction, the image decoding apparatus 100 can determine the encoding units 430a, 430b, and 430c by dividing the current encoding unit 400 in the horizontal direction. Also, when the current encoding unit 450 is in the horizontal direction, the image decoding apparatus 100 can determine the encoding units 480a, 480b, and 480c by dividing the current encoding unit 450 in the vertical direction.

According to an exemplary embodiment, the image decoding apparatus 100 may determine an odd number of encoding units included in the current encoding unit 400 or 450, and the sizes of the determined encoding units may not be the same. For example, the size of a predetermined encoding unit 430b or 480b among the determined odd number of encoding units 430a, 430b, 430c, 480a, 480b, and 480c is different from the size of the other encoding units 430a, 430c, 480a, and 480c . That is, an encoding unit that can be determined by dividing the current encoding unit (400 or 450) may have a plurality of types of sizes, and an odd number of encoding units (430a, 430b, 430c, 480a, 480b, 480c) May have different sizes.

According to one embodiment, when the information on the split mode mode indicates that an encoding unit is divided into an odd number of blocks, the image decoding apparatus 100 can determine an odd number of encoding units included in the current encoding unit 400 or 450 Further, the image decoding apparatus 100 may limit the encoding unit of at least one of odd number of encoding units generated by division. Referring to FIG. 4, the image decoding apparatus 100 includes a coding unit 430a, 430b, 430c, 480a, 480b, and 480c, which are generated by dividing a current coding unit 400 or 450, The decoding process for the coding units 430b and 480b may be different from the coding units 430a, 430c, 480a, and 480c. For example, in the video decoding apparatus 100, the encoding units 430b and 480b positioned at the center are restricted so as not to be further divided unlike the other encoding units 430a, 430c, 480a, and 480c, It can be limited to be divided.

FIG. 5 illustrates a process in which the image decoding apparatus 100 divides an encoding unit based on at least one of information on a block type information and a division mode mode according to an embodiment.

According to an embodiment, the image decoding apparatus 100 determines whether to divide or not divide the square-shaped first coding unit 500 into coding units based on at least one of information on the block type information and the information on the division mode mode . When the information on the split mode mode indicates that the first encoding unit 500 is divided in the horizontal direction according to an embodiment, the image decoding apparatus 100 divides the first encoding unit 500 in the horizontal direction, 2 encoding unit 510, as shown in FIG. The first encoding unit, the second encoding unit, and the third encoding unit used according to an embodiment are terms used to understand the relation before and after the division between encoding units. For example, if the first encoding unit is divided, the second encoding unit can be determined, and if the second encoding unit is divided, the third encoding unit can be determined. Hereinafter, the relationship between the first coding unit, the second coding unit and the third coding unit used can be understood to be in accordance with the above-mentioned characteristic.

According to one embodiment, the image decoding apparatus 100 may determine that the determined second encoding unit 510 is not divided or divided into encoding units based on at least one of the block type information and the information on the split mode mode . Referring to FIG. 5, the image decoding apparatus 100 includes a second encoding unit (not shown) of a non-square shape determined by dividing a first encoding unit 500 based on at least one of information on block type information and information on a split mode 510) may be divided into at least one third encoding unit 520a, 520b, 520c, 520d, or the second encoding unit 510 may not be divided. The image decoding apparatus 100 may acquire at least one of the block type information and the information on the split mode mode and the image decoding apparatus 100 may acquire at least one of the block type information and the split mode mode The second encoding unit 510 may divide the first encoding unit 500 into a plurality of second encoding units of various types (for example, 510), and the second encoding unit 510 may divide the block type information and the information The first encoding unit 500 may be divided according to a manner in which the first encoding unit 500 is divided. When the first encoding unit 500 is divided into the second encoding units 510 based on at least one of the block type information for the first encoding unit 500 and the information about the split mode mode 520b, 520c, and 520d (e.g., 520a, 520b, 520c, and 520d) based on at least one of the block type information on the second encoding unit 510 and the information on the split mode mode, Etc.). That is, the encoding unit may be recursively divided based on at least one of the information on the split mode mode and the block type information associated with each of the encoding units. Therefore, a square encoding unit may be determined in a non-square encoding unit, and a non-square encoding unit may be determined by dividing the square encoding unit recursively.

Referring to FIG. 5, among the odd third encoding units 520b, 520c, 520d in which the non-square second encoding unit 510 is divided and determined, predetermined encoding units (for example, An encoding unit or a square-shaped encoding unit) can be recursively divided. According to an exemplary embodiment, the square-shaped third coding unit 520b, which is one of the odd-numbered third coding units 520b, 520c, and 520d, may be divided in the horizontal direction and divided into a plurality of fourth coding units. The non-square fourth encoding unit 530b or 530d, which is one of the plurality of fourth encoding units 530a, 530b, 530c, and 530d, may be further divided into a plurality of encoding units. For example, the fourth encoding unit 530b or 530d in the non-square form may be divided again into odd number of encoding units. A method which can be used for recursive division of an encoding unit will be described later in various embodiments.

According to one embodiment, the image decoding apparatus 100 divides each of the third encoding units 520a, 520b, 520c, and 520d into units of encoding based on at least one of information on the block type information and the information on the split mode mode . Also, the image decoding apparatus 100 may determine that the second encoding unit 510 is not divided based on at least one of the block type information and the information on the split mode mode. The image decoding apparatus 100 may divide the non-square second encoding unit 510 into odd third encoding units 520b, 520c and 520d according to an embodiment. The image decoding apparatus 100 may set a predetermined restriction on a predetermined third encoding unit among odd numbered third encoding units 520b, 520c, and 520d. For example, the image decoding apparatus 100 may limit the number of encoding units 520c located in the middle among odd numbered third encoding units 520b, 520c, and 520d to no longer be divided, or be divided into a set number of times .

Referring to FIG. 5, the image decoding apparatus 100 includes an encoding unit (not shown) located in the middle among odd third encoding units 520b, 520c, and 520d included in the second encoding unit 510 in the non- 520c may not be further divided or may be limited to being divided into a predetermined division form (for example, divided into four coding units only or divided into a form corresponding to a form in which the second coding units 510 are divided) (For example, dividing only n times, n > 0). The above restriction on the coding unit 520c positioned at the center is merely an example and should not be construed to be limited to the above embodiments and the coding unit 520c positioned at the center is not limited to the coding units 520b and 520d Quot;), < / RTI > which can be decoded differently.

According to an embodiment, the image decoding apparatus 100 may acquire at least one of the block type information and the division type mode information used for dividing the current encoding unit at a predetermined position in the current encoding unit.

FIG. 6 illustrates a method by which the image decoding apparatus 100 determines a predetermined encoding unit among odd number of encoding units according to an embodiment.

Referring to FIG. 6, at least one of the block type information of the current encoding units 600 and 650 and the information of the split mode mode is a sample of a predetermined position among a plurality of samples included in the current encoding units 600 and 650 For example, samples 640 and 690 positioned in the middle). However, the predetermined position in the current encoding unit 600 in which at least one of the block type information and the information on the split mode mode can be obtained should not be limited to the middle position shown in FIG. 6, It should be understood that various positions (e.g., top, bottom, left, right, top left, bottom left, top right, or bottom right, etc.) that may be included in unit 600 may be included. The image decoding apparatus 100 may determine that the current encoding unit is divided or not divided into the encoding units of various types and sizes by acquiring at least one of the block type information obtained from the predetermined position and the information on the division mode mode .

According to an exemplary embodiment, when the current encoding unit is divided into a predetermined number of encoding units, the image decoding apparatus 100 may select one of the encoding units. The method for selecting one of the plurality of encoding units may be various, and description of these methods will be described later in various embodiments.

According to an exemplary embodiment, the image decoding apparatus 100 may divide the current encoding unit into a plurality of encoding units and determine a predetermined encoding unit.

According to an exemplary embodiment, the image decoding apparatus 100 may use information indicating the positions of odd-numbered encoding units in order to determine an encoding unit located in the middle among odd-numbered encoding units. 6, the image decoding apparatus 100 divides the current encoding unit 600 or the current encoding unit 650 into odd number of encoding units 620a, 620b, 620c or odd number of encoding units 660a, 660b, and 660c. The image decoding apparatus 100 may use the information on the positions of the odd-numbered encoding units 620a, 620b, and 620c or the odd-numbered encoding units 660a, 660b, and 660c, (660b). For example, the image decoding apparatus 100 determines the positions of the encoding units 620a, 620b, and 620c based on information indicating the positions of predetermined samples included in the encoding units 620a, 620b, and 620c, The encoding unit 620b located in the encoding unit 620b can be determined. Specifically, the video decoding apparatus 100 encodes the encoding units 620a, 620b, and 620c based on information indicating the positions of the upper left samples 630a, 630b, and 630c of the encoding units 620a, 620b, and 620c, The encoding unit 620b located in the center can be determined.

Information indicating the positions of the upper left samples 630a, 630b, and 630c included in the coding units 620a, 620b, and 620c according to one embodiment is stored in the pictures of the coding units 620a, 620b, and 620c Or information about the position or coordinates of the object. Information indicating the positions of the upper left samples 630a, 630b, and 630c included in the coding units 620a, 620b, and 620c according to one embodiment is stored in the coding units 620a , 620b, and 620c, and the width or height may correspond to information indicating the difference between the coordinates of the encoding units 620a, 620b, and 620c in the picture. That is, the image decoding apparatus 100 directly uses the information on the position or the coordinates in the picture of the coding units 620a, 620b, and 620c or the information on the width or height of the coding unit corresponding to the difference value between the coordinates The encoding unit 620b located in the center can be determined.

According to one embodiment, the information indicating the position of the upper left sample 630a of the upper coding unit 620a may indicate the coordinates (xa, ya) and the upper left sample 530b of the middle coding unit 620b May indicate the coordinates (xb, yb), and the information indicating the position of the upper left sample 630c of the lower coding unit 620c may indicate the coordinates (xc, yc). The video decoding apparatus 100 can determine the center encoding unit 620b using the coordinates of the upper left samples 630a, 630b, and 630c included in the encoding units 620a, 620b, and 620c. For example, when the coordinates of the upper left samples 630a, 630b, and 630c are sorted in ascending or descending order, the coding unit 620b including (xb, yb) coordinates of the sample 630b located at the center, Can be determined as a coding unit located in the middle of the coding units 620a, 620b, and 620c determined by dividing the current coding unit 600. [ However, the coordinates indicating the positions of the samples 630a, 630b and 630c in the upper left corner may indicate the coordinates indicating the absolute position in the picture, and the position of the upper left sample 630a of the upper coding unit 620a may be (Dxb, dyb), which is information indicating the relative position of the sample 630b at the upper left of the middle encoding unit 620b, and the relative position of the sample 630c at the upper left of the lower encoding unit 620c Information dyn (dxc, dyc) coordinates may also be used. Also, the method of determining the coding unit at a predetermined position by using the coordinates of the sample as information indicating the position of the sample included in the coding unit should not be limited to the above-described method, and various arithmetic Should be interpreted as a method.

The image decoding apparatus 100 may divide the current encoding unit 600 into a plurality of encoding units 620a, 620b, and 620c and may encode a predetermined one of the encoding units 620a, 620b, and 620c The encoding unit can be selected according to the criterion. For example, the image decoding apparatus 100 can select an encoding unit 620b having a different size from among the encoding units 620a, 620b, and 620c.

According to an embodiment, the image decoding apparatus 100 may include (xa, ya) coordinates, which is information indicating the position of the upper left sample 630a of the upper encoding unit 620a, a sample of the upper left sample of the middle encoding unit 620b (Xc, yc) coordinates, which is information indicating the position of the lower-stage coding unit 630b and the position of the upper-left sample 630c of the lower-stage coding unit 620c, , 620b, and 620c, respectively. The image decoding apparatus 100 encodes the encoding units 620a and 620b using the coordinates (xa, ya), (xb, yb), (xc, yc) indicating the positions of the encoding units 620a, 620b and 620c , And 620c, respectively. According to an embodiment, the image decoding apparatus 100 may determine the width of the upper encoding unit 620a as the width of the current encoding unit 600. [ The image decoding apparatus 100 can determine the height of the upper encoding unit 620a as yb-ya. The image decoding apparatus 100 may determine the width of the middle encoding unit 620b as the width of the current encoding unit 600 according to an embodiment. The image decoding apparatus 100 can determine the height of the middle encoding unit 620b as yc-yb. The image decoding apparatus 100 may determine the width or height of the lower coding unit by using the width or height of the current coding unit and the width and height of the upper coding unit 620a and the middle coding unit 620b . The image decoding apparatus 100 may determine an encoding unit having a different size from other encoding units based on the widths and heights of the determined encoding units 620a, 620b, and 620c. Referring to FIG. 6, the image decoding apparatus 100 may determine a coding unit 620b as a coding unit at a predetermined position while having a size different from that of the upper coding unit 620a and the lower coding unit 620c. However, the process of determining the encoding unit having a size different from that of the other encoding units by the video decoding apparatus 100 may be the same as that of the first embodiment in which the encoding unit of a predetermined position is determined using the size of the encoding unit determined based on the sample coordinates , Various processes may be used for determining the encoding unit at a predetermined position by comparing the sizes of the encoding units determined according to predetermined sample coordinates.

The video decoding apparatus 100 determines the position (xd, yd) which is the information indicating the position of the upper left sample 670a of the left encoding unit 660a and the position (xd, yd) of the sample 670b at the upper left of the middle encoding unit 660b 660b and 660c using the (xf, yf) coordinates, which is information indicating the (xe, ye) coordinate which is the information indicating the position of the right encoding unit 660c and the position of the sample 670c at the upper left of the right encoding unit 660c, Each width or height can be determined. The image decoding apparatus 100 encodes the encoded units 660a and 660b using the coordinates (xd, yd), (xe, ye), (xf, yf) indicating the positions of the encoding units 660a, 660b and 660c And 660c, respectively.

According to an embodiment, the image decoding apparatus 100 may determine the width of the left encoding unit 660a as xe-xd. The image decoding apparatus 100 can determine the height of the left encoding unit 660a as the height of the current encoding unit 650. [ According to an embodiment, the image decoding apparatus 100 may determine the width of the middle encoding unit 660b as xf-xe. The image decoding apparatus 100 can determine the height of the middle encoding unit 660b as the height of the current encoding unit 600. [ The image decoding apparatus 100 may determine that the width or height of the right encoding unit 660c is less than the width or height of the current encoding unit 650 and the width and height of the left encoding unit 660a and the middle encoding unit 660b . ≪ / RTI > The image decoding apparatus 100 may determine an encoding unit having a different size from the other encoding units based on the widths and heights of the determined encoding units 660a, 660b, and 660c. Referring to FIG. 6, the image decoding apparatus 100 may determine a coding unit 660b as a coding unit at a predetermined position while having a size different from that of the left coding unit 660a and the right coding unit 660c. However, the process of determining the encoding unit having a size different from that of the other encoding units by the video decoding apparatus 100 may be the same as that of the first embodiment in which the encoding unit of a predetermined position is determined using the size of the encoding unit determined based on the sample coordinates , Various processes may be used for determining the encoding unit at a predetermined position by comparing the sizes of the encoding units determined according to predetermined sample coordinates.

However, the position of the sample to be considered for determining the position of the coding unit should not be interpreted as being limited to the left upper end, and information about the position of any sample included in the coding unit can be interpreted as being available.

According to one embodiment, the image decoding apparatus 100 can select a coding unit at a predetermined position among the odd number of coding units determined by dividing the current coding unit considering the type of the current coding unit. For example, if the current coding unit is a non-square shape having a width greater than the height, the image decoding apparatus 100 can determine a coding unit at a predetermined position along the horizontal direction. That is, the image decoding apparatus 100 may determine one of the encoding units which are located in the horizontal direction and limit the encoding unit. If the current coding unit is a non-square shape having a height greater than the width, the image decoding apparatus 100 can determine a coding unit at a predetermined position in the vertical direction. That is, the image decoding apparatus 100 may determine one of the encoding units having different positions in the vertical direction and set a restriction on the encoding unit.

According to an exemplary embodiment, the image decoding apparatus 100 may use information indicating positions of even-numbered encoding units in order to determine an encoding unit at a predetermined position among the even-numbered encoding units. The image decoding apparatus 100 may determine an even number of coding units by binary coding the current coding unit and determine a coding unit at a predetermined position by using information on the positions of the even number of coding units. A concrete procedure for this is omitted because it may be a process corresponding to a process of determining a coding unit of a predetermined position (e.g., the middle position) among the odd number of coding units described with reference to FIG.

According to one embodiment, when a non-square current encoding unit is divided into a plurality of encoding units, in order to determine an encoding unit at a predetermined position among a plurality of encoding units, Can be used. For example, in order to determine a coding unit located in the middle among the plurality of coding units in which the current coding unit is divided, the video decoding apparatus 100 may determine the block type information stored in the sample included in the middle coding unit, Mode may be used.

6, the image decoding apparatus 100 divides the current encoding unit 600 into a plurality of encoding units 620a, 620b, and 620c based on at least one of information on the block type information and the information on the split mode mode And the encoding unit 620b located in the middle of the plurality of encoding units 620a, 620b, and 620c can be determined. Furthermore, the image decoding apparatus 100 may determine the coding unit 620b located at the center in consideration of the position at which at least one of the block type information and the division type mode information is obtained. That is, at least one of the block type information of the current encoding unit 600 and the information of the division mode mode can be obtained in the sample 640 located in the middle of the current encoding unit 600, If the current encoding unit 600 is divided into a plurality of encoding units 620a, 620b, and 620c based on at least one of the information on the division mode mode and the encoding unit 620b including the sample 640, As shown in FIG. The information used for determining the encoding unit located in the middle should not be limited to at least one of the block type information and the information about the division mode mode, and a process of determining an encoding unit in which various types of information are located in the middle ≪ / RTI >

According to an embodiment, predetermined information for identifying a coding unit at a predetermined position may be obtained from a predetermined sample included in a coding unit to be determined. Referring to FIG. 6, the image decoding apparatus 100 includes a plurality of encoding units 620a, 620b, and 620c that are determined by dividing a current encoding unit 600, (For example, a sample located in the middle of the current encoding unit 600) at a predetermined position in the current encoding unit 600 in order to determine an encoding unit located in the middle of the encoding unit, And at least one of information on the split mode mode may be used. That is, the image decoding apparatus 100 can determine the sample at the predetermined position in consideration of the block form of the current encoding unit 600, and the image decoding apparatus 100 can determine a plurality of A coding unit 620b including samples from which predetermined information (for example, at least one of information on the block type information and the division mode information) can be obtained from the plurality of coding units 620a, 620b, and 620c So that a predetermined limit can be set. Referring to FIG. 6, the image decoding apparatus 100 may determine a sample 640 located in the center of a current encoding unit 600 as a sample from which predetermined information can be obtained, The coding unit 100 may limit the coding unit 620b including the sample 640 to a predetermined limit in the decoding process. However, the position of the sample from which the predetermined information can be obtained should not be construed to be limited to the above-mentioned position, but may be interpreted as samples at arbitrary positions included in the encoding unit 620b to be determined for limiting.

The position of a sample from which predetermined information can be obtained according to one embodiment may be determined according to the type of the current encoding unit 600. [ According to one embodiment, the block type information can determine whether the current encoding unit is a square or a non-square, and determine the position of a sample from which predetermined information can be obtained according to the shape. For example, the video decoding apparatus 100 may use at least one of the information on the width of the current coding unit and the information on the height to position at least one of the width and the height of the current coding unit in half The sample can be determined as a sample from which predetermined information can be obtained. For example, when the block type information related to the current encoding unit is a non-square type, the image decoding apparatus 100 selects one of the samples adjacent to the boundary dividing the longer side of the current encoding unit into halves by a predetermined Can be determined as a sample from which the information of < / RTI >

According to an exemplary embodiment, when the current encoding unit is divided into a plurality of encoding units, the image decoding apparatus 100 may determine the encoding unit of a predetermined position among the plurality of encoding units, Information can be used. According to an exemplary embodiment, the image decoding apparatus 100 may acquire at least one of information on the block type information and the information on the division mode mode from a sample of a predetermined position included in the encoding unit, The plurality of coding units generated by dividing the unit may be divided using at least one of the information on the division mode and the block type information obtained from the sample at the predetermined position included in each of the plurality of the coding units. That is, the coding unit can be recursively divided using at least one of the block type information obtained in the sample at the predetermined position included in each of the coding units and the information about the division mode. Since the recursive division process of the encoding unit has been described with reference to FIG. 5, a detailed description thereof will be omitted.

According to an embodiment, the image decoding apparatus 100 can determine at least one encoding unit by dividing the current encoding unit, and the order in which the at least one encoding unit is decoded is determined as a predetermined block (for example, ). ≪ / RTI >

FIG. 7 illustrates a sequence in which a plurality of coding units are processed when the image decoding apparatus 100 determines a plurality of coding units by dividing a current coding unit according to an exemplary embodiment.

According to one embodiment, the image decoding apparatus 100 determines the second encoding units 710a and 710b by dividing the first encoding unit 700 in the vertical direction according to information on the block type information and the division mode, The second encoding units 730a and 730b may be determined by dividing the first encoding units 700a to 750c by dividing the first encoding units 700a and 750b in the horizontal direction to divide the first encoding units 700 in the vertical direction and the horizontal direction, , 750d can be determined.

Referring to FIG. 7, the image decoding apparatus 100 may determine the order in which the second encoding units 710a and 710b determined by dividing the first encoding unit 700 in the vertical direction are processed in the horizontal direction 710c . The image decoding apparatus 100 may determine the processing order of the second encoding units 730a and 730b determined by dividing the first encoding unit 700 in the horizontal direction as the vertical direction 730c. The image decoding apparatus 100 processes the encoding units located in one row of the second encoding units 750a, 750b, 750c and 750d determined by dividing the first encoding unit 700 in the vertical direction and the horizontal direction, (For example, a raster scan order or a z scan order 750e) in which the encoding units located in the next row are processed.

According to an embodiment, the image decoding apparatus 100 may recursively divide encoding units. 7, the image decoding apparatus 100 may determine a plurality of encoding units 710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d by dividing the first encoding unit 700, The determined plurality of encoding units 710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d can be recursively divided. The method of dividing the plurality of encoding units 710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d may be a method corresponding to the method of dividing the first encoding unit 700. [ Accordingly, the plurality of encoding units 710a, 710b, 730a, 730b, 750a, 750b, 750c, and 750d may be independently divided into a plurality of encoding units. Referring to FIG. 7, the image decoding apparatus 100 can determine the second encoding units 710a and 710b by dividing the first encoding unit 700 in the vertical direction, and can further determine the second encoding units 710a and 710b Can be determined not to divide or separate independently.

The image decoding apparatus 100 may divide the second encoding unit 710a on the left side in the horizontal direction into the third encoding units 720a and 720b and the second encoding units 710b ) May not be divided.

According to an embodiment, the processing order of the encoding units may be determined based on the division process of the encoding units. In other words, the processing order of the divided coding units can be determined based on the processing order of the coding units immediately before being divided. The image decoding apparatus 100 can determine the order in which the third encoding units 720a and 720b determined by dividing the second encoding unit 710a on the left side are processed independently of the second encoding unit 710b on the right side. The third encoding units 720a and 720b may be processed in the vertical direction 720c because the second encoding units 710a on the left side are divided in the horizontal direction and the third encoding units 720a and 720b are determined. Since the order in which the left second encoding unit 710a and the right second encoding unit 710b are processed corresponds to the horizontal direction 710c, the third encoding unit 710a included in the left second encoding unit 710a, The right encoding unit 710b can be processed after the blocks 720a and 720b are processed in the vertical direction 720c. The above description is intended to explain the process sequence in which encoding units are determined according to the encoding units before division. Therefore, it should not be construed to be limited to the above-described embodiments, It should be construed as being used in various ways that can be handled independently in sequence.

8 illustrates a process of determining that the current encoding unit is divided into odd number of encoding units when the image decoding apparatus 100 can not process the encoding units in a predetermined order according to an embodiment.

According to an embodiment, the image decoding apparatus 100 may determine that the current encoding unit is divided into odd number of encoding units based on the obtained block type information and information on the split mode mode. Referring to FIG. 8, the first encoding unit 800 of a square shape may be divided into second non-square encoding units 810a and 810b, and the second encoding units 810a and 810b may be independently 3 encoding units 820a, 820b, 820c, 820d, and 820e. According to an embodiment, the image decoding apparatus 100 can determine the plurality of third encoding units 820a and 820b by dividing the left encoding unit 810a of the second encoding unit in the horizontal direction, and the right encoding unit 810b Can be divided into an odd number of third encoding units 820c, 820d, and 820e.

According to an exemplary embodiment, the image decoding apparatus 100 determines whether or not the third encoding units 820a, 820b, 820c, 820d, and 820e can be processed in a predetermined order and determines whether there are odd- You can decide. 8, the image decoding apparatus 100 may recursively divide the first encoding unit 800 to determine the third encoding units 820a, 820b, 820c, 820d, and 820e. The video decoding apparatus 100 may further include a first coding unit 800, a second coding unit 810a and 810b or a third coding unit 820a and 820b based on at least one of information on the block type information and the information on the division mode mode , 820c, 820d, and 820e are divided into odd number of coding units among the divided types. For example, an encoding unit located on the right of the second encoding units 810a and 810b may be divided into odd third encoding units 820c, 820d, and 820e. The order in which the plurality of coding units included in the first coding unit 800 are processed may be a predetermined order (for example, a z-scan order 830) 100 can determine whether the third encoding units 820c, 820d, and 820e determined by dividing the right second encoding unit 810b into odd numbers satisfy the condition that the third encoding units 820c, 820d, and 820e can be processed according to the predetermined order.

According to an embodiment, the image decoding apparatus 100 satisfies a condition that third encoding units 820a, 820b, 820c, 820d, and 820e included in the first encoding unit 800 can be processed in a predetermined order And it is determined whether or not at least one of the widths and heights of the second encoding units 810a and 810b is divided in half according to the boundaries of the third encoding units 820a, 820b, 820c, 820d, and 820e, . For example, the third encoding units 820a and 820b, which are determined by dividing the height of the left second encoding unit 810a in the non-square shape by half, can satisfy the condition. The boundaries of the third encoding units 820c, 820d, and 820e determined by dividing the right second encoding unit 810b into three encoding units do not divide the width or height of the right second encoding unit 810b in half , The third encoding units 820c, 820d, and 820e may be determined as not satisfying the condition. The image decoding apparatus 100 may determine that the scan order is disconnection in the case of such unsatisfactory condition and determine that the right second encoding unit 810b is divided into odd number of encoding units based on the determination result. According to an embodiment, the image decoding apparatus 100 may limit a coding unit of a predetermined position among the divided coding units when the coding unit is divided into odd number of coding units. Since the embodiment has been described above, a detailed description thereof will be omitted.

FIG. 9 illustrates a process in which the image decoding apparatus 100 determines at least one encoding unit by dividing a first encoding unit 900 according to an embodiment.

According to one embodiment, the image decoding apparatus 100 may divide the first encoding unit 900 based on at least one of the block type information obtained through the bitstream obtaining unit 110 and the information on the split mode mode have. The first coding unit 900 in the form of a square may be divided into four coding units having a square form, or may be divided into a plurality of non-square coding units. For example, referring to FIG. 9, when the block type information indicates that the first encoding unit 900 is square, and the information on the split mode mode is divided into non-square encoding units, the image decoding apparatus 100 1 encoding unit 900 into a plurality of non-square encoding units. Specifically, when the information on the split mode mode indicates that the first encoding unit 900 is divided horizontally or vertically to determine an odd number of encoding units, the image decoding apparatus 100 performs a first encoding The unit 900 can be divided into the second coding units 910a, 910b and 910c divided in the vertical direction as the odd number of coding units or the second coding units 920a, 920b and 920c divided in the horizontal direction .

According to an embodiment, the image decoding apparatus 100 may be configured such that the second encoding units 910a, 910b, 910c, 920a, 920b, and 920c included in the first encoding unit 900 are processed in a predetermined order And the condition is that at least one of the width and the height of the first encoding unit 900 is divided in half according to the boundaries of the second encoding units 910a, 910b, 910c, 920a, 920b, and 920c . 9, the boundaries of the second encoding units 910a, 910b, and 910c, which are determined by vertically dividing the first encoding unit 900 in a square shape, are divided in half by the width of the first encoding unit 900 The first encoding unit 900 can be determined as not satisfying a condition that can be processed in a predetermined order. In addition, since the boundaries of the second encoding units 920a, 920b, and 920c, which are determined by dividing the first encoding unit 900 in the horizontal direction into the horizontal direction, can not divide the width of the first encoding unit 900 in half, 1 encoding unit 900 may be determined as not satisfying a condition that can be processed in a predetermined order. The image decoding apparatus 100 may determine that the scan sequence is disconnection in the case of such unsatisfactory condition and determine that the first encoding unit 900 is divided into odd number of encoding units based on the determination result. According to an embodiment, the image decoding apparatus 100 may limit a coding unit of a predetermined position among the divided coding units when the coding unit is divided into odd number of coding units. Since the embodiment has been described above, a detailed description thereof will be omitted.

According to an embodiment, the image decoding apparatus 100 may determine various types of encoding units by dividing the first encoding unit.

Referring to FIG. 9, the image decoding apparatus 100 may divide a first coding unit 900 in a square form, a first coding unit 930 or 950 in a non-square form into various types of coding units .

10 is a diagram illustrating a case where a second encoding unit of a non-square type determined by dividing a first encoding unit 1000 by a video decoding apparatus 100 satisfies a predetermined condition according to an embodiment, Lt; RTI ID = 0.0 > limited. ≪ / RTI >

According to an exemplary embodiment, the image decoding apparatus 100 may include a first encoding unit 1000 in the form of a square based on at least one of block type information and division mode information acquired through the bitstream obtaining unit 110 It may be determined to divide into non-square second encoding units 1010a, 1010b, 1020a, and 1020b. The second encoding units 1010a, 1010b, 1020a, and 1020b may be independently divided. Accordingly, the image decoding apparatus 100 divides or divides the image data into a plurality of encoding units based on at least one of the block type information and the division type mode information related to each of the second encoding units 1010a, 1010b, 1020a, and 1020b You can decide not to. According to an embodiment, the image decoding apparatus 100 divides the left second encoding unit 1010a in a non-square form determined by dividing the first encoding unit 1000 in the vertical direction into a horizontal direction, 1012a, and 1012b. In the case where the left second encoding unit 1010a is divided in the horizontal direction, the right-side second encoding unit 1010b is arranged in the horizontal direction in the same manner as the direction in which the left second encoding unit 1010a is divided, As shown in Fig. If the right second encoding unit 1010b is divided in the same direction and the third encoding units 1014a and 1014b are determined, the left second encoding unit 1010a and the right second encoding unit 1010b are arranged in the horizontal direction The third encoding units 1012a, 1012b, 1014a, and 1014b can be determined by being independently divided. However, the image decoding apparatus 100 may divide the first encoding unit 1000 into four square-shaped second encoding units 1030a, 1030b, 1030c, and 1030d based on at least one of the block type information and the information on the split mode mode ), Which may be inefficient in terms of image decoding.

According to an embodiment, the image decoding apparatus 100 divides a second encoding unit 1020a or 1020b in a non-square form determined by dividing a first encoding unit 1000 in a horizontal direction into a vertical direction, (1022a, 1022b, 1024a, 1024b). However, when one of the second encoding units (for example, the upper second encoding unit 1020a) is divided in the vertical direction, the image decoding apparatus 100 may be configured to encode the second encoding unit (for example, The encoding unit 1020b) can be restricted such that the upper second encoding unit 1020a can not be divided vertically in the same direction as the divided direction.

FIG. 11 illustrates a process in which the image decoding apparatus 100 divides a square-shaped encoding unit when the information on the split mode mode can not be shown to be divided into four square-shaped encoding units according to an embodiment .

According to one embodiment, the image decoding apparatus 100 divides the first encoding unit 1100 based on at least one of information on the block type information and the information on the split mode mode to generate second encoding units 1110a, 1110b, 1120a, and 1120b Etc.) can be determined. The information on the division type mode may include information on various types in which the coding unit can be divided, but information on various types may not include information for dividing into four square units of coding units. According to the information on the split mode mode, the image decoding apparatus 100 can not divide the first encoding unit 1100 in the square form into the second encoding units 1130a, 1130b, 1130c, and 1130d in the form of four squares . The image decoding apparatus 100 may determine the second encoding units 1110a, 1110b, 1120a, and 1120b in the non-square form based on the information on the split mode mode.

According to an exemplary embodiment, the image decoding apparatus 100 may independently divide the non-square second encoding units 1110a, 1110b, 1120a, and 1120b, respectively. Each of the second encoding units 1110a, 1110b, 1120a, and 1120b may be divided in a predetermined order through a recursive method, and the first encoding units 1110a, 1110b, 1120a, and 1120b may be divided according to at least one of the block type information, May be a division method corresponding to how the unit 1100 is divided.

For example, the image decoding apparatus 100 can determine the third encoding units 1112a and 1112b in the form of a square by dividing the left second encoding unit 1110a in the horizontal direction and the right second encoding unit 1110b It is possible to determine the third encoding units 1114a and 1114b in the form of a square by being divided in the horizontal direction. Furthermore, the image decoding apparatus 100 may divide the left second encoding unit 1110a and the right second encoding unit 1110b in the horizontal direction to determine the third encoding units 1116a, 1116b, 1116c, and 1116d in the form of a square have. In this case, the encoding unit can be determined in the same manner as the first encoding unit 1100 is divided into the four second square encoding units 1130a, 1130b, 1130c, and 1130d.

 In another example, the image decoding apparatus 100 can determine the third encoding units 1122a and 1122b in the form of a square by dividing the upper second encoding unit 1120a in the vertical direction, and the lower second encoding units 1120b May be divided in the vertical direction to determine the third encoding units 1124a and 1124b in the form of a square. Further, the image decoding apparatus 100 may divide the upper second encoding unit 1120a and the lower second encoding unit 1120b in the vertical direction to determine the square-shaped third encoding units 1126a, 1126b, 1126a, and 1126b have. In this case, the encoding unit can be determined in the same manner as the first encoding unit 1100 is divided into the four second square encoding units 1130a, 1130b, 1130c, and 1130d.

FIG. 12 illustrates that the processing order among a plurality of coding units may be changed according to a division process of a coding unit according to an exemplary embodiment.

According to an embodiment, the image decoding apparatus 100 may divide the first encoding unit 1200 based on information on the block type information and the split mode mode. When the block type information indicates a square shape and the information on the split mode mode indicates that the first encoding unit 1200 is divided into at least one of a horizontal direction and a vertical direction, The unit 1200 can be divided to determine the second encoding unit (e.g., 1210a, 1210b, 1220a, 1220b, etc.). Referring to FIG. 12, the non-square second encoding units 1210a, 1210b, 1220a, and 1220b, which are determined by dividing the first encoding unit 1200 only in the horizontal direction or the vertical direction, Can be independently divided based on information on the < / RTI > For example, the image decoding apparatus 100 divides the second encoding units 1210a and 1210b, which are generated by dividing the first encoding unit 1200 in the vertical direction, in the horizontal direction, and outputs the third encoding units 1216a, 1216b, 1216c and 1216d can be determined and the second encoding units 1220a and 1220b generated by dividing the first encoding unit 1200 in the horizontal direction are divided in the horizontal direction and the third encoding units 1226a, , 1226d. Since the process of dividing the second encoding units 1210a, 1210b, 1220a, and 1220b has been described above with reference to FIG. 11, a detailed description thereof will be omitted.

According to an embodiment, the image decoding apparatus 100 may process an encoding unit in a predetermined order. The features of the processing of the encoding unit in the predetermined order have been described in detail with reference to FIG. 7, and a detailed description thereof will be omitted. 12, the image decoding apparatus 100 divides a first encoding unit 1200 of a square shape into 4 pieces of fourth encoding units 1216a, 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, 1226d Can be determined. According to an embodiment, the image decoding apparatus 100 may process the third encoding units 1216a, 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, and 1226d according to the form in which the first encoding unit 1200 is divided You can decide.

According to an embodiment, the image decoding apparatus 100 divides the generated second encoding units 1210a and 1210b in the vertical direction and divides them in the horizontal direction to determine third encoding units 1216a, 1216b, 1216c, and 1216d And the image decoding apparatus 100 first processes the third encoding units 1216a and 1216c included in the left second encoding unit 1210a in the vertical direction and then processes the third encoding units 1216a and 1216c included in the second right encoding unit 1210b The third encoding units 1216a, 1216b, 1216c, and 1216d can be processed according to the order 1217 of processing the third encoding units 1216b and 1216d in the vertical direction.

According to an embodiment, the image decoding apparatus 100 divides the second encoding units 1220a and 1220b generated in the horizontal direction into vertical directions to determine the third encoding units 1226a, 1226b, 1226c and 1226d And the image decoding apparatus 100 first processes the third encoding units 1226a and 1226b included in the upper second encoding unit 1220a in the horizontal direction and then encodes the third encoding units 1226a and 1226b included in the lower second encoding unit 1220b The third encoding units 1226a, 1226b, 1226c, and 1226d may be processed in accordance with an order 1227 for processing the third encoding units 1226c and 1226d in the horizontal direction.

Referring to FIG. 12, the second encoding units 1210a, 1210b, 1220a, and 1220b are divided to determine the third encoding units 1216a, 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, and 1226d, have. The second encoding units 1210a and 1210b determined to be divided in the vertical direction and the second encoding units 1220a and 1220b determined to be divided in the horizontal direction are divided into different formats, but the third encoding units 1216a , 1216b, 1216c, 1216d, 1226a, 1226b, 1226c, and 1226d, the result is that the first encoding unit 1200 is divided into the same type of encoding units. Accordingly, the image decoding apparatus 100 recursively divides the encoding units based on at least one of the block type information and the information on the division type mode, thereby eventually determining the same type of encoding units, A plurality of encoding units may be processed in different orders.

FIG. 13 illustrates a process of determining the depth of an encoding unit according to a change in type and size of an encoding unit when a plurality of encoding units are determined by recursively dividing an encoding unit according to an embodiment.

According to an exemplary embodiment, the image decoding apparatus 100 may determine the depth of a coding unit according to a predetermined criterion. For example, a predetermined criterion may be a length of a long side of a coding unit. When the length of the long side of the current encoding unit is divided by 2n (n > 0) times longer than the length of the long side of the current encoding unit, the depth of the current encoding unit is smaller than the depth of the encoding unit before being divided it can be determined that the depth is increased by n. Hereinafter, an encoding unit with an increased depth is expressed as a lower-depth encoding unit.

13, based on block type information (e.g., block type information may indicate '0: SQUARE') indicating a square shape according to an embodiment, the image decoding apparatus 100 may generate a square 1 encoding unit 1300 can be divided to determine the second encoding unit 1302, the third encoding unit 1304, etc. of the lower depth. If the size of the first encoding unit 1300 in the form of a square is 2Nx2N, the second encoding unit 1302 determined by dividing the width and height of the first encoding unit 1300 by 1/2 may have a size of NxN have. Further, the third encoding unit 1304 determined by dividing the width and height of the second encoding unit 1302 by a half size may have a size of N / 2xN / 2. In this case, the width and height of the third encoding unit 1304 correspond to 1/4 of the first encoding unit 1300. If the depth of the first encoding unit 1300 is D, the depth of the second encoding unit 1302, which is half the width and height of the first encoding unit 1300, may be D + 1, The depth of the third encoding unit 1304, which is one fourth of the width and height of the third encoding unit 1300, may be D + 2.

According to an exemplary embodiment, block type information indicating a non-square shape (for example, block type information is' 1: NS_VER 'indicating that the height is a non-square having a width greater than the width or' 2 >), the image decoding apparatus 100 divides the first coding unit 1310 or 1320 in a non-square form into a second coding unit 1312 or 1322 of a lower depth, The third encoding unit 1314 or 1324, or the like.

The image decoding apparatus 100 may determine a second coding unit (for example, 1302, 1312, 1322, etc.) by dividing at least one of the width and the height of the first coding unit 1310 of Nx2N size. That is, the image decoding apparatus 100 can determine the second encoding unit 1302 of NxN size or the second encoding unit 1322 of NxN / 2 size by dividing the first encoding unit 1310 in the horizontal direction, It is also possible to determine the second encoding unit 1312 of N / 2xN size by dividing it in the horizontal direction and the vertical direction.

According to an embodiment, the image decoding apparatus 100 divides at least one of a width and a height of a 2NxN first encoding unit 1320 to determine a second encoding unit (e.g., 1302, 1312, 1322, etc.) It is possible. That is, the image decoding apparatus 100 can determine the second encoding unit 1302 of NxN size or the second encoding unit 1312 of N / 2xN size by dividing the first encoding unit 1320 in the vertical direction, The second encoding unit 1322 of the NxN / 2 size may be determined by dividing the image data in the horizontal direction and the vertical direction.

According to one embodiment, the image decoding apparatus 100 divides at least one of the width and the height of the second encoding unit 1302 of NxN size to determine a third encoding unit (for example, 1304, 1314, 1324, etc.) It is possible. That is, the image decoding apparatus 100 determines the third encoding unit 1304 of N / 2xN / 2 size by dividing the second encoding unit 1302 in the vertical direction and the horizontal direction, or determines the third encoding unit 1304 of N / 4xN / 3 encoding unit 1314 or a third encoding unit 1324 of N / 2xN / 4 size.

The image decoding apparatus 100 may divide at least one of the width and the height of the second encoding unit 1312 of N / 2xN size into a third encoding unit (e.g., 1304, 1314, 1324, etc.) . That is, the image decoding apparatus 100 divides the second encoding unit 1312 in the horizontal direction to generate a third encoding unit 1304 of N / 2xN / 2 or a third encoding unit 1324 of N / 2xN / 4 size ) Or may be divided in the vertical and horizontal directions to determine the third encoding unit 1314 of N / 4xN / 2 size.

According to an exemplary embodiment, the image decoding apparatus 100 divides at least one of the width and the height of the second encoding unit 1322 of NxN / 2 size to generate a third encoding unit 1304, 1314, 1324, . That is, the image decoding apparatus 100 divides the second encoding unit 1322 in the vertical direction to generate a third encoding unit 1304 of N / 2xN / 2 or a third encoding unit 1314 of N / 4xN / 2 size ) Or may be divided in the vertical and horizontal directions to determine the third encoding unit 1324 of N / 2xN / 4 size.

According to an embodiment, the image decoding apparatus 100 may divide a square-shaped encoding unit (for example, 1300, 1302, and 1304) into a horizontal direction or a vertical direction. For example, the first encoding unit 1300 having a size of 2Nx2N is divided in the vertical direction to determine a first encoding unit 1310 having a size of Nx2N or the first encoding unit 1310 having a size of 2NxN to determine a first encoding unit 1320 having a size of 2NxN . According to an exemplary embodiment, when the depth is determined based on the length of the longest side of the encoding unit, the depth of the encoding unit, which is determined by dividing the first encoding unit 1300 of 2Nx2N size in the horizontal direction or the vertical direction, May be the same as the depth of the unit (1300).

According to one embodiment, the width and height of the third encoding unit 1314 or 1324 may correspond to one fourth of the first encoding unit 1310 or 1320. [ When the depth of the first coding unit 1310 or 1320 is D, the depth of the second coding unit 1312 or 1322 which is half the width and height of the first coding unit 1310 or 1320 is D + And the depth of the third encoding unit 1314 or 1324, which is one fourth of the width and height of the first encoding unit 1310 or 1320, may be D + 2.

FIG. 14 illustrates a depth index (hereinafter referred to as PID) for coding unit classification and depth that can be determined according to the type and size of coding units according to an exemplary embodiment.

According to an embodiment, the image decoding apparatus 100 may divide the first encoding unit 1400 in a square form to determine various types of second encoding units. 14, the image decoding apparatus 100 divides a first encoding unit 1400 into at least one of a vertical direction and a horizontal direction according to information on a division mode mode, and outputs the second encoding units 1402a and 1402b , 1404a, 1404b, 1406a, 1406b, 1406c, 1406d. That is, the image decoding apparatus 100 determines the second encoding units 1402a, 1402b, 1404a, 1404b, 1406a, 1406b, 1406c, and 1406d based on the information on the split mode mode for the first encoding unit 1400 .

The second encoding units 1402a, 1402b, 1404a, 1404b, 1406a, 1406b, 1406c, and 1406d, which are determined according to the information on the split mode mode for the first encoding unit 1400 in the square form, The depth can be determined based on the length of the sides. For example, since the length of one side of the first encoding unit 1400 in the square form is the same as the length of long sides of the second encoding units 1402a, 1402b, 1404a, and 1404b in the non-square form, 1400) and the non-square type second encoding units 1402a, 1402b, 1404a, 1404b are denoted by D in the same manner. On the other hand, when the image decoding apparatus 100 divides the first encoding unit 1400 into four square-shaped second encoding units 1406a, 1406b, 1406c, and 1406d based on the information on the split mode mode, The length of one side of the second encoding units 1406a, 1406b, 1406c and 1406d in the form of the second encoding units 1406a, 1406b, 1406c and 1406d is 1/2 of the length of one side of the first encoding unit 1400, May be a depth of D + 1 that is one depth lower than D, which is the depth of the first encoding unit 1400.

According to an exemplary embodiment, the image decoding apparatus 100 divides a first encoding unit 1410 having a height greater than a width in a horizontal direction according to information on a split mode, and generates a plurality of second encoding units 1412a and 1412b , 1414a, 1414b, and 1414c. According to an embodiment, the image decoding apparatus 100 divides a first encoding unit 1420 of a shape whose width is longer than a height in a vertical direction according to information on a division mode, and generates a plurality of second encoding units 1422a and 1422b , 1424a, 1424b, 1424c.

1412b, 1414a, 1414b, 1414c. 1422a, 1422b, 1414c, 1414b, 1414c, 1414b, 1414c, 1414b, 1414c, 1424a, 1424b, 1424c can be determined in depth based on the length of the long side. For example, since the length of one side of the square-shaped second encoding units 1412a and 1412b is 1/2 times the length of one side of the non-square first encoding unit 1410 whose height is longer than the width, The depth of the second encoding units 1412a and 1412b of the form is D + 1 which is one depth lower than the depth D of the first encoding unit 1410 of the non-square form.

Furthermore, the image decoding apparatus 100 may divide the non-square first coding unit 1410 into odd second coding units 1414a, 1414b and 1414c based on the information on the division mode mode. The odd number of second encoding units 1414a, 1414b and 1414c may include non-square second encoding units 1414a and 1414c and a square second encoding unit 1414b. In this case, the length of the long sides of the non-square type second encoding units 1414a and 1414c and the length of one side of the second encoding unit 1414b in the square form are set to 1/10 of the length of one side of the first encoding unit 1410, The depth of the second encoding units 1414a, 1414b, and 1414c may be a depth of D + 1 which is one depth lower than D, which is the depth of the first encoding unit 1410. [ The image decoding apparatus 100 is connected to the first encoding unit 1420 in the form of a non-square shape whose width is longer than the height in a manner corresponding to the scheme for determining the depths of the encoding units associated with the first encoding unit 1410 The depth of the encoding units can be determined.

According to an exemplary embodiment, the image decoding apparatus 100 determines an index (PID) for distinguishing the divided coding units. If the odd-numbered coding units are not the same size, The index can be determined based on the index. 14, an encoding unit 1414b positioned at the center among the odd-numbered encoding units 1414a, 1414b, and 1414c has the same width as other encoding units 1414a and 1414c, Lt; / RTI > 1414a and 1414c. That is, in this case, the encoding unit 1414b positioned in the middle may include two of the other encoding units 1414a and 1414c. Therefore, if the index (PID) of the coding unit 1414b positioned at the center is 1 according to the scanning order, the coding unit 1414c positioned next to the coding unit 1414c may be three days in which the index is increased by two. That is, there may be a discontinuity in the value of the index. According to an exemplary embodiment, the image decoding apparatus 100 may determine whether odd-numbered encoding units are not the same size based on the presence or absence of an index discontinuity for distinguishing between the divided encoding units.

According to an exemplary embodiment, the image decoding apparatus 100 may determine whether the image is divided into a specific division form based on an index value for distinguishing a plurality of coding units divided from the current coding unit. 14, the image decoding apparatus 100 divides a first coding unit 1410 of a rectangular shape whose height is longer than the width to determine an even number of coding units 1412a and 1412b or an odd number of coding units 1414a and 1414b , And 1414c. The image decoding apparatus 100 may use an index (PID) indicating each coding unit in order to distinguish each of the plurality of coding units. According to one embodiment, the PID may be obtained at a sample of a predetermined position of each coding unit (e.g., the upper left sample).

According to an embodiment, the image decoding apparatus 100 may determine a coding unit of a predetermined position among the coding units determined by using the index for classifying the coding unit. According to an embodiment, when the information on the division type mode for the rectangular first type encoding unit 1410 whose height is longer than the width is divided into three encoding units, the image decoding apparatus 100 may encode the first encoding unit 1410 can be divided into three coding units 1414a, 1414b, 1414c. The image decoding apparatus 100 can assign an index to each of the three encoding units 1414a, 1414b, and 1414c. The image decoding apparatus 100 may compare the indexes of the respective encoding units in order to determine the middle encoding unit among the encoding units divided into odd numbers. The image decoding apparatus 100 encodes an encoding unit 1414b having an index corresponding to a middle value among the indices based on the indices of the encoding units by encoding the middle position among the encoding units determined by dividing the first encoding unit 1410 Can be determined as a unit. According to an exemplary embodiment, the image decoding apparatus 100 may determine an index based on a size ratio between coding units when the coding units are not the same size in determining the index for dividing the divided coding units . 14, the coding unit 1414b generated by dividing the first coding unit 1410 is divided into coding units 1414a and 1414c having the same width as the other coding units 1414a and 1414c but different in height Can be double the height. In this case, if the index (PID) of the coding unit 1414b positioned at the center is 1, the coding unit 1414c located next to the coding unit 1414c may be three days in which the index is increased by two. In this case, when the index increases uniformly and the increment increases, the image decoding apparatus 100 may determine that the image decoding apparatus 100 is divided into a plurality of encoding units including encoding units having different sizes from other encoding units. , The image decoding apparatus 100 determines that the encoding unit (for example, the middle encoding unit) at a predetermined position among the odd number of encoding units is different from the encoding unit for the odd number of encoding units and the size Can divide the current encoding unit into other forms. In this case, the image decoding apparatus 100 may determine an encoding unit having a different size by using an index (PID) for the encoding unit. However, the index and the size or position of the encoding unit at a predetermined position to be determined are specific for explaining an embodiment, and thus should not be construed to be limited thereto, and various indexes, positions and sizes of encoding units can be used Should be interpreted.

According to an exemplary embodiment, the image decoding apparatus 100 may use a predetermined data unit in which a recursive division of an encoding unit starts.

FIG. 15 illustrates that a plurality of coding units are determined according to a plurality of predetermined data units included in a picture according to an embodiment.

According to an embodiment, a predetermined data unit may be defined as a unit of data in which an encoding unit starts to be recursively segmented using at least one of block type information and information on a division mode mode. That is, it may correspond to a coding unit of the highest depth used in the process of determining a plurality of coding units for dividing the current picture. Hereinafter, such a predetermined data unit is referred to as a reference data unit for convenience of explanation.

According to one embodiment, the reference data unit may represent a predetermined size and shape. According to one embodiment, the reference encoding unit may comprise samples of MxN. Here, M and N may be equal to each other, or may be an integer represented by a multiplier of 2. That is, the reference data unit may represent a square or a non-square shape, and may be divided into an integer number of encoding units.

According to an embodiment, the image decoding apparatus 100 may divide the current picture into a plurality of reference data units. According to an exemplary embodiment, the image decoding apparatus 100 may divide a plurality of reference data units for dividing a current picture into pieces using information on a division type mode for each reference data unit. The segmentation process of the reference data unit may correspond to the segmentation process using a quad-tree structure.

According to an exemplary embodiment, the image decoding apparatus 100 may determine in advance a minimum size that the reference data unit included in the current picture can have. Accordingly, the image decoding apparatus 100 can determine reference data units of various sizes having a size of a minimum size or more, and use at least one of the block type information and the division mode mode information based on the determined reference data unit The encoding unit can be determined.

Referring to FIG. 15, the image decoding apparatus 100 may use a square-shaped reference encoding unit 1500 or a non-square-shaped reference encoding unit 1502. According to an exemplary embodiment, the type and size of the reference encoding unit may include various data units (e.g., a sequence, a picture, a slice, a slice segment a slice segment, a maximum encoding unit, and the like).

According to one embodiment, the bitstream obtaining unit 110 of the video decoding apparatus 100 obtains at least one of the information on the type of the reference encoding unit and the size of the reference encoding unit from the bitstream for each of the various data units can do. The process of determining at least one encoding unit included in the reference type encoding unit 1500 is described in detail in the process of dividing the current encoding unit 300 of FIG. 3, and the non- Is determined in the process of dividing the current encoding unit 400 or 450 of FIG. 4, so that a detailed description thereof will be omitted.

In order to determine the size and the type of the reference encoding unit according to a predetermined data unit predetermined based on a predetermined condition, the image decoding apparatus 100 may include an index for identifying the size and type of the reference encoding unit Can be used. That is, the bitstream obtaining unit 110 obtains a predetermined condition (for example, a size of a slice or less) of the various data units (for example, a sequence, a picture, a slice, a slice segment, Data unit), it is possible to obtain only an index for identification of the size and type of the reference encoding unit for each slice, slice segment, maximum encoding unit, and the like. The image decoding apparatus 100 can determine the size and shape of the reference data unit for each data unit satisfying the predetermined condition by using the index. When the information on the type of the reference encoding unit and the information on the size of the reference encoding unit are obtained from the bitstream for each relatively small data unit and used, the use efficiency of the bitstream may not be good. Therefore, Information on the size of the reference encoding unit and information on the size of the reference encoding unit can be acquired and used. In this case, at least one of the size and the type of the reference encoding unit corresponding to the index indicating the size and type of the reference encoding unit may be predetermined. That is, the image decoding apparatus 100 selects at least one of the size and the type of the reference encoding unit in accordance with the index, thereby obtaining at least one of the size and the type of the reference encoding unit included in the data unit, You can decide.

According to an exemplary embodiment, the image decoding apparatus 100 may use at least one reference encoding unit included in one maximum encoding unit. That is, the maximum encoding unit for dividing an image may include at least one reference encoding unit, and the encoding unit may be determined through a recursive division process of each reference encoding unit. According to an exemplary embodiment, at least one of the width and the height of the maximum encoding unit may correspond to at least one integer multiple of the width and height of the reference encoding unit. According to an exemplary embodiment, the size of the reference encoding unit may be a size obtained by dividing the maximum encoding unit n times according to a quadtree structure. In other words, the image decoding apparatus 100 can determine the reference encoding unit by dividing the maximum encoding unit n times according to the quad tree structure, and determine the reference encoding unit as the block type information and the information about the split mode Based on at least one of them.

16 shows a processing block serving as a reference for determining a determination order of a reference encoding unit included in a picture 1600 according to an embodiment.

According to one embodiment, the image decoding apparatus 100 may determine at least one processing block for dividing a picture. The processing block is a data unit including at least one reference encoding unit for dividing an image, and at least one reference encoding unit included in the processing block may be determined in a specific order. That is, the order of determination of at least one reference encoding unit determined in each processing block may correspond to one of various kinds of order in which the reference encoding unit can be determined, and the reference encoding unit determination order determined in each processing block May be different for each processing block. The order of determination of the reference encoding unit determined for each processing block is a raster scan, a Z scan, an N scan, an up-right diagonal scan, a horizontal scan a horizontal scan, and a vertical scan. However, the order that can be determined should not be limited to the scan orders.

According to an embodiment, the image decoding apparatus 100 may obtain information on the size of the processing block and determine the size of the at least one processing block included in the image. The image decoding apparatus 100 may obtain information on the size of the processing block from the bitstream to determine the size of the at least one processing block included in the image. The size of such a processing block may be a predetermined size of a data unit represented by information on the size of the processing block.

According to an embodiment, the bitstream obtaining unit 110 of the video decoding apparatus 100 may obtain information on the size of the processing block from the bitstream for each specific data unit. For example, information on the size of a processing block can be obtained from a bitstream in units of data such as an image, a sequence, a picture, a slice, a slice segment, and the like. That is, the bitstream obtaining unit 110 may obtain information on the size of the processing block from the bitstream for each of the plurality of data units, and the image decoding apparatus 100 may use the obtained information on the size of the processing block The size of the at least one processing block to be divided may be determined, and the size of the processing block may be an integer multiple of the reference encoding unit.

According to an embodiment, the image decoding apparatus 100 may determine the sizes of the processing blocks 1602 and 1612 included in the picture 1600. For example, the video decoding apparatus 100 can determine the size of the processing block based on information on the size of the processing block obtained from the bitstream. Referring to FIG. 16, the image decoding apparatus 100 according to an exemplary embodiment of the present invention may be configured such that the horizontal size of the processing blocks 1602 and 1612 is four times the horizontal size of the reference encoding unit, four times the vertical size of the reference encoding unit, You can decide. The image decoding apparatus 100 may determine an order in which at least one reference encoding unit is determined in at least one processing block.

According to one embodiment, the video decoding apparatus 100 may determine each processing block 1602, 1612 included in the picture 1600 based on the size of the processing block, and may include in the processing blocks 1602, 1612 The determination order of at least one reference encoding unit is determined. The determination of the reference encoding unit may include determining the size of the reference encoding unit according to an embodiment.

According to an exemplary embodiment, the image decoding apparatus 100 may obtain information on a determination order of at least one reference encoding unit included in at least one processing block from a bitstream, So that the order in which at least one reference encoding unit is determined can be determined. The information on the decision order can be defined in the order or direction in which the reference encoding units are determined in the processing block. That is, the order in which the reference encoding units are determined may be independently determined for each processing block.

According to one embodiment, the image decoding apparatus 100 may obtain information on a determination order of a reference encoding unit from a bitstream for each specific data unit. For example, the bitstream obtaining unit 110 may obtain information on a determination order of a reference encoding unit from a bitstream for each data unit such as an image, a sequence, a picture, a slice, a slice segment, and a processing block. Since the information on the determination order of the reference encoding unit indicates the reference encoding unit determination order in the processing block, the information on the determination order can be obtained for each specific data unit including an integer number of processing blocks.

The image decoding apparatus 100 may determine at least one reference encoding unit based on the determined order according to an embodiment.

According to an exemplary embodiment, the bitstream obtaining unit 110 may obtain information on a reference encoding unit determination order from the bitstream as information related to the processing blocks 1602 and 1612, and the image decoding apparatus 100 may obtain It is possible to determine the order of determining at least one reference encoding unit included in the processing blocks 1602 and 1612 and determine at least one reference encoding unit included in the picture 1600 according to the determination order of the encoding units. Referring to FIG. 16, the image decoding apparatus 100 may determine a determination order 1604 and 1614 of at least one reference encoding unit associated with each of the processing blocks 1602 and 1612. For example, when information on the order of determination of the reference encoding unit is obtained for each processing block, the reference encoding unit determination order associated with each processing block 1602, 1612 may be different for each processing block. If the reference encoding unit determination order 1604 related to the processing block 1602 is a raster scan order, the reference encoding unit included in the processing block 1602 can be determined according to the raster scan order. On the other hand, when the reference encoding unit determination order 1614 related to the other processing block 1612 is a reverse order of the raster scan order, the reference encoding unit included in the processing block 1612 can be determined according to the reverse order of the raster scan order.

The image decoding apparatus 100 may decode the determined at least one reference encoding unit according to an embodiment. The image decoding apparatus 100 can decode an image based on the reference encoding unit determined through the above-described embodiment. The method of decoding the reference encoding unit may include various methods of decoding the image.

According to an embodiment, the image decoding apparatus 100 may obtain block type information indicating a type of a current encoding unit or information on a split mode mode indicating a method of dividing a current encoding unit from a bitstream. Information about the block type information or the split mode mode may be included in a bitstream related to various data units. For example, the video decoding apparatus 100 may include a sequence parameter set, a picture parameter set, a video parameter set, a slice header, a slice segment header slice block type information included in the segment header or information on the split mode mode can be used. Furthermore, the image decoding apparatus 100 may obtain a syntax element corresponding to information on the maximum encoding unit, the reference encoding unit, the block format information from the bit stream, or the split format mode for each processing block from the bit stream and use the syntax element.

FIG. 17 shows coding units that can be determined for each picture when combinations of types in which coding units can be divided according to an embodiment are different from picture to picture.

Referring to FIG. 17, the image decoding apparatus 100 may determine a combination of division types in which a coding unit can be divided for each picture differently. For example, the video decoding apparatus 100 may include a picture 1700 that can be divided into four coding units out of at least one pictures included in the video, a picture 1710 that can be divided into two or four coding units ) And a picture 1720 that can be divided into two, three, or four encoding units. The image decoding apparatus 100 may use only division type information indicating that the picture 1700 is divided into four square encoding units in order to divide the picture 1700 into a plurality of encoding units. The image decoding apparatus 100 may use only division type information indicating division into two or four coding units in order to divide the picture 1710. [ The image decoding apparatus 100 may use only division type information indicating division into two, three or four coding units in order to divide the picture 1720. [ Since the combination of divisional types described above is merely an example for explaining the operation of the video decoding apparatus 100, the combination of the divisional types described above should not be construed to be limited to the above embodiments, It should be understood that combinations of shapes can be used.

According to an embodiment, the bitstream obtaining unit 110 of the video decoding apparatus 100 may convert a bitstream including an index indicating a combination of division type information into a predetermined data unit (e.g., a sequence, a picture, a slice, ). For example, the bitstream obtaining unit 110 may obtain an index indicating a combination of segment type information in a sequence parameter set, a picture parameter set, or a slice header . The video decoding apparatus 100 of the video decoding apparatus 100 can determine a combination of division types in which a coding unit can be divided for each predetermined data unit by using the acquired index, A combination of division types can be used.

18 illustrates various types of coding units that can be determined based on the division type information that can be represented by a binary code according to an embodiment.

According to an embodiment, the image decoding apparatus 100 may divide a coding unit into various types using block type information and division type information acquired through the bitstream obtaining unit 110. [ The type of the encoding unit that can be divided may correspond to various types including the types described in the above embodiments.

Referring to FIG. 18, the image decoding apparatus 100 may divide a square-shaped encoding unit into at least one of a horizontal direction and a vertical direction based on the division type information, and may divide the non- Direction or vertical direction.

According to an embodiment, when the image decoding apparatus 100 divides a square-shaped encoding unit into horizontal and vertical directions and divides it into four square-shaped encoding units, division type information for a square encoding unit is represented There are four possible partition types. According to an exemplary embodiment, the partition type information may be represented by a two-digit binary code, and a binary code may be allocated to each partition type. For example, if the coding unit is not divided, the division type information can be expressed by (00) b, and when the coding unit is divided into the horizontal direction and the vertical direction, the division type information can be represented by (01) b, When the coding unit is divided in the horizontal direction, the division type information can be expressed by (10) b, and when the coding unit is divided in the vertical direction, the division type information can be expressed by (11) b.

According to an exemplary embodiment, when the non-square type coding unit is divided into horizontal or vertical directions, the image decoding apparatus 100 may classify the types of division types that can be represented by the division type information into several encoding units Can be determined. Referring to FIG. 18, the image decoding apparatus 100 may divide up to three non-square encoding units according to an embodiment. The image decoding apparatus 100 may divide an encoding unit into two encoding units. In this case, the division type information may be expressed by (10) b. The image decoding apparatus 100 may divide an encoding unit into three encoding units. In this case, the division type information may be expressed by (11) b. The video decoding apparatus 100 can determine that the encoding unit is not divided, and in this case, the division type information can be expressed by (0) b. That is, the video decoding apparatus 100 may use VLC (Varyable Length Coding) instead of Fixed Length Coding (FLC) in order to use a binary code indicating division type information.

Referring to FIG. 18, according to an embodiment, a binary code of division type information indicating that an encoding unit is not divided can be expressed by (0) b. If the binary code of the division type information indicating that the encoding unit is not divided is set to (00) b, even though the division type information set in (01) b is absent, all of the binary codes of the 2-bit division type information Should be used. However, as shown in FIG. 18, when three division types for non-square type coding units are used, the image decoding apparatus 100 uses 1-bit binary code (0) b as the division type information It is possible to determine that the encoding unit is not divided, so that the bit stream can be efficiently used. However, the division form of the non-square type coding unit represented by the division type information should not be construed to be limited to only the three types shown in FIG. 18, but should be interpreted in various forms including the above-described embodiments.

Figure 19 shows another form of an encoding unit that can be determined based on partition type information that can be represented in binary code according to one embodiment.

Referring to FIG. 19, the image decoding apparatus 100 can divide a square-shaped encoding unit into horizontal or vertical directions based on the division type information, divide a non-square encoding unit horizontally or vertically can do. That is, the division type information can indicate that a square-shaped encoding unit is divided in one direction. In this case, the binary code of the division type information indicating that the square type encoding unit is not divided can be expressed by (0) b. If the binary code of the division type information indicating that the encoding unit is not divided is set to (00) b, even though the division type information set in (01) b is absent, all of the binary codes of the 2-bit division type information Should be used. However, as shown in FIG. 19, in the case of using three division types for a square-shaped encoding unit, the image decoding apparatus 100 can use the 1-bit binary code (0) b as the division type information, It can be determined that the unit is not divided, so that the bit stream can be used efficiently. However, the division type of the square type encoding unit represented by the division type information should not be construed to be limited only to the three types shown in FIG. 19, and should be interpreted in various forms including the above-described embodiments.

According to one embodiment, the block type information or the division type information can be expressed using a binary code, and this information can be immediately generated as a bit stream. In addition, the block type information or the division type information that can be represented by the binary code may not be directly generated as a bitstream but may be used as a binary code to be input in context adaptive binary arithmetic coding (CABAC).

The image decoding apparatus 100 according to an exemplary embodiment of the present invention will now be described with reference to a process of obtaining a syntax for block type information or division type information through CABAC. The bitstream obtaining unit 110 may obtain a bitstream including a binary code for the syntax. The image decoding apparatus 100 can detect a syntax element indicating block type information or division type information by inverse binarizing the bin string included in the acquired bit stream. According to an embodiment, the image decoding apparatus 100 may obtain a set of binary bin strings corresponding to a syntax element to be decoded, decode each bin using probability information, and the image decoding apparatus 100 may decode You can iterate until the empty string consisting of the empty beans is equal to one of the previously obtained empty strings. The image decoding apparatus 100 can determine the syntax element by performing inverse binarization of the bin string.

According to an embodiment, the image decoding apparatus 100 may decode an adaptive binary arithmetic coding to determine a syntax for an empty string, and the image decoding apparatus 100 may include a bitstream obtaining unit Lt; RTI ID = 0.0 > 110 < / RTI > Referring to FIG. 18, the bitstream obtaining unit 110 of the video decoding apparatus 100 may obtain a bitstream representing a binary code indicating division type information according to an embodiment. The image decoding apparatus 100 can determine the syntax for the division type information using the obtained binary code having a size of 1 bit or 2 bits. The video decoding apparatus 100 may update the probability for each bit of the 2-bit binary code to determine the syntax for the division type information. That is, the image decoding apparatus 100 can update the probability of having a value of 0 or 1 when decoding the next bin, depending on whether the value of the first bin of the 2-bit binary code is 0 or 1.

According to an exemplary embodiment, the image decoding apparatus 100 may update the probability of bins used in decoding the bins of the empty string for the syntax in the process of determining the syntax, and the image decoding apparatus 100 may update It can be determined that the certain bit of the empty string has the same probability without updating the probability.

Referring to FIG. 18, in the process of determining a syntax using an empty string indicating division type information for a non-square type encoding unit, the image decoding apparatus 100 does not divide a non-square type encoding unit The syntax for the division type information can be determined using one bin having a value of 0. That is, when the block type information indicates that the current encoding unit is a non-square type, the first bin of the bin string for the division type information is 0 when the non-square type encoding unit is not divided, and 2 or 3 And may be 1 when it is divided into coding units. Accordingly, the probability that the first bin of the bin string of the partition type information for the non-square encoding unit is 0 may be 1/3, and the probability of 1 day may be 2/3. As described above, the image decoding apparatus 100 can represent only a 1-bit empty string having a value of 0 as the division type information indicating that the non-square type encoding unit is not divided. Therefore, The syntax for the division type information can be determined by determining whether the second bin is 0 or 1 only when the first bin of the type information is 1. According to an exemplary embodiment, the image decoding apparatus 100 may decode a bin if the first bin of the partition type information is 1, and the probability of the second bin being 0 or 1 is equal to each other.

According to an exemplary embodiment, the image decoding apparatus 100 may use various probabilities for each bin in the process of determining a bin of an empty string for the partition type information. According to an exemplary embodiment, the image decoding apparatus 100 may determine the probability of the bin for the partition type information according to the direction of the non-square block. According to an embodiment, the image decoding apparatus 100 may determine the probability of the bin for the division type information differently according to the width of the current encoding unit or the length of the long side. According to an exemplary embodiment, the image decoding apparatus 100 may determine the probability of the bin for the division type information according to at least one of the type of the current encoding unit and the length of the long side.

According to an embodiment, the image decoding apparatus 100 can determine the probability of the bin for the division type information to be the same for the encoding units of a predetermined size or larger. For example, it can be determined that the probability of a bin for division type information is the same for encoding units of 64 samples or more based on the length of the long side of the encoding unit.

According to an embodiment, the image decoding apparatus 100 may determine an initial probability for bins constituting an empty string of the division type information based on a slice type (for example, I slice, P slice or B slice ...) .

20 is a block diagram of an image encoding and decoding system performing loop filtering.

The encoding unit 2010 of the image encoding and decoding system 2000 transmits the encoded bit stream of the image and the decoding unit 2050 receives and decodes the bit stream to output the reconstructed image. Here, the encoding stage 2010 may be similar to the image encoding device 200 described later, and the decoding stage 2050 may be similar to the image decoding device 100. [

In the encoding stage 2010, the predictive encoding unit 2015 outputs a reference image through inter-prediction and intra-prediction, and the transform and quantization unit 2020 transforms the residual data between the reference image and the current input image into a quantized transform coefficient And outputs the quantized signal. The entropy encoding unit 2025 encodes the quantized transform coefficients, converts the quantized transform coefficients, and outputs them as a bit stream. The quantized transform coefficients are reconstructed into spatial domain data through an inverse quantization and inverse transform unit 2030 and the reconstructed spatial domain data is output as a reconstructed image through a deblocking filtering unit 2035 and a loop filtering unit 2040 do. The reconstructed image can be used as a reference image of the next input image through the predictive encoding unit 2015.

The coded image data of the bitstream received by the decoding unit 2050 is restored into residual data of the spatial domain through an entropy decoding unit 2055 and an inverse quantization and inverse transform unit 2060. The deblocking filtering unit 2065 and the loop filtering unit 2070 perform filtering on the image data in the spatial domain by combining the reference image and the residual data output from the predictive decoding unit 2075, And output a restored image of the current original image. The reconstructed image may be used as a reference image for the next original image by the predictive decoding unit 2075. [

The loop filtering unit 2040 of the encoding unit 2010 performs loop filtering using the input filter information according to a user input or a system setting. The filter information used by the loop filtering unit 2040 is output to the entropy encoding unit 2010 and is transmitted to the decoding unit 2050 together with the encoded image data. The loop filtering unit 2070 of the decoding unit 2050 may perform loop filtering based on the filter information input from the decoding unit 2050.

FIG. 21 is a diagram illustrating an example of filtering units included in the maximum encoding unit according to an exemplary embodiment, and filtering performing information of the filtering unit.

The filtering units of the loop filtering unit 2040 of the encoding stage 2010 and the loop filtering unit 2070 of the decoding stage 2050 are similar to the encoding units according to the embodiment described above with reference to FIGS. The filter information may include block type information and division type information of a data unit for indicating a filtering unit and loop filtering performance information indicating whether to perform loop filtering on the filtering unit.

The filtering units included in the maximum coding unit 2100 according to an exemplary embodiment may have the same block type and division type as the coding units included in the maximum coding unit 2100. [ In addition, the filtering units included in the maximum encoding unit 2100 according to an exemplary embodiment may be divided based on the sizes of the encoding units included in the maximum encoding unit 2100. For example, referring to FIG. 21, the filtering units include a square-shaped filtering unit 2140 having a depth D, non-square filtering units 2132 and 2134 having a depth D, a square filtering unit 2134 having a depth D + Square filtering units 2162 and 2166 of depth D + 1 and square filtering units 2122, 2124, 2126 and 2128 of depth D + 2 ).

The block type information, the division type information (depth), and the loop filtering performance information of the filtering units included in the maximum encoding unit 2100 can be encoded as shown in Table 1 below.

The process of recursively dividing an encoding unit according to block type information and block division information according to an embodiment to determine a plurality of encoding units is as described above with reference to FIG. The loop filtering performance information of the filtering units according to an exemplary embodiment indicates that loop filtering is performed for the corresponding filtering unit when the flag value is 1, and indicates that loop filtering is not performed when the flag value is 0. [ Referring to Table 1, information of a data unit for determining a filtering unit to be filtered by the loop filtering units 2040 and 2070 can be all encoded as filter information and transmitted.

Since the coding units configured according to an embodiment are coding units configured to minimize the error with the original image, it is expected that the spatial correlation in the coding unit is high. Therefore, the filtering unit may be determined based on the encoding unit according to the embodiment, so that the operation of determining the filtering unit separately from the determination of the encoding unit may be omitted. In addition, since the information for determining the division type of the filtering unit can be omitted by determining the filtering unit based on the encoding unit according to the embodiment, the transmission bit rate of the filter information can be saved.

In the above-described embodiment, the filtering unit is determined based on the encoding unit according to the embodiment. However, the filtering unit is divided based on the encoding unit, May be determined.

The determination of the filtering unit disclosed in the above embodiments can be applied not only to loop filtering but also to various embodiments such as deblocking filtering, adaptive loop filtering, and the like.

According to an exemplary embodiment, the image decoding apparatus 100 may divide the current encoding unit using at least one of the block type information and the division type information, and the block type information is determined in advance to use only the square type, Can be determined in advance to indicate that it is not divided or can be divided into four square-shaped encoding units. That is, according to the block type information of the current coding unit, the coding unit always has a square shape, and can be divided into four or four square-shaped coding units based on the division type information. The video decoding apparatus 100 can use the block form and the division form only to acquire a bitstream generated using a predetermined encoding method through the bitstream obtaining unit 110, Only a predetermined block type and division type can be used. In this case, the image decoding apparatus 100 can solve the compatibility problem with a predetermined encoding method by using a predetermined decoding method similar to the predetermined encoding method. According to one embodiment, when the image decoding apparatus 100 uses the predetermined decoding method using only a predetermined block type and division type among various types of block type information and division type information that can be represented, The image decoding apparatus 100 can omit the process of obtaining block type information from the bitstream. A syntax indicating whether or not to use the predetermined decoding method described above can be used. The syntax may be a bitstream for each of various types of data units that can include a plurality of coding units such as a sequence, a picture, a slice unit, Lt; / RTI > That is, the bitstream obtaining unit 110 can determine whether to obtain a syntax indicating block type information from a bitstream based on a syntax indicating whether or not a predetermined decoding method is used.

FIG. 23 shows an index according to a Z scan sequence of an encoding unit according to an embodiment.

The image decoding apparatus 100 according to an exemplary embodiment may scan the lower data units included in the upper data unit according to the Z scan order. In addition, the image decoding apparatus 100 according to an embodiment can sequentially access data according to a Z-scan index within a coding unit included in a maximum coding unit or a processing block.

The image decoding apparatus 100 according to an embodiment can divide a reference encoding unit into at least one encoding unit as described above with reference to FIG. 3 to FIG. At this time, square-shaped encoding units and non-square-shaped encoding units may be mixed in the reference encoding unit. The image decoding apparatus 100 according to an exemplary embodiment may perform data access according to a Z scan index included in each encoding unit in the reference encoding unit. In this case, the method of applying the Z scan index may be different depending on whether or not a non-square type encoding unit exists in the reference encoding unit.

According to an exemplary embodiment, when a non-square type encoding unit does not exist in the reference encoding unit, encoding units of lower depth in the reference encoding unit may have a continuous Z scan index. For example, according to one embodiment, an encoding unit of a higher depth may include four encoding units of a lower depth. Here, the coding units of four sub-depths may be contiguous with each other, and the coding units of each sub-depth may be scanned in the Z scan order according to the index indicating the Z scanning order. The index indicating the Z scan order according to one embodiment may be set to a number that increases in accordance with the Z scan order for each encoding unit. In this case, it is possible to scan the depth-based encoding units of the same depth according to the Z scan order.

According to one embodiment, when at least one non-square type encoding unit exists in the reference encoding unit, the image decoding apparatus 100 divides encoding units in the reference encoding unit into subblocks, The blocks can be scanned according to the Z scan order. For example, if there is a non-square encoding unit in the vertical or horizontal direction within the reference encoding unit, the Z scan can be performed using the divided sub-blocks. In addition, for example, when division is performed in odd number of encoding units within a reference encoding unit, Z scans can be performed using sub-blocks. The subblock may be a square in which an encoding unit or an arbitrary encoding unit that is not further divided is divided. For example, four square-shaped sub-blocks may be divided from a square-shaped encoding unit. Also, for example, two square-shaped subblocks can be divided from a non-square-shaped encoding unit.

Referring to FIG. 23, for example, an apparatus 100 for decoding an image according to an exemplary embodiment decodes encoded units 2302, 2304, 2306, 2308, and 2310 of lower depth in an encoding unit 2300 in a Z scan order As shown in FIG. The encoding unit 2300 and the encoding units 2302, 2304, 2306, 2308, and 2310 are relatively higher encoding units and lower encoding units, respectively. The encoding unit 2300 includes horizontal non-square encoding units 2306 and 2310. These non-square-shaped encoding units 2306 and 2310 are discontinuous with the adjacent square-shaped encoding units 2302 and 2304. In addition, the coding unit 2308 is a square unit, and the coding unit of the non-square type is an odd-numbered coding unit located at the middle of the division. Like the non-square-shaped encoding units 2306 and 2310, the encoding unit 2308 is discontinuous with the adjacent square-shaped encoding units 2302 and 2304. When the non-square type coding units 2306 and 2310 are included in the coding unit 2300 or when the non-square type coding units are included in the odd numbered coding units 2308, Since adjacent borders are discontinuous, a continuous Z scan index can not be set. Accordingly, the image decoding apparatus 100 can continuously set the Z scan index by dividing the encoding units into sub-blocks. In addition, the image decoding apparatus 100 may perform a continuous Z scan on a coding unit 2308 positioned in the middle of a non-square type coding unit 2306 or 2310 or a non-square type coding unit divided into an odd number Can be performed.

The coding unit 2320 shown in FIG. 23 is obtained by dividing the coding units 2302, 2304, 2306, 2308, and 2310 in the coding unit 2300 into sub-blocks. Since a Z scan index can be set for each of the subblocks, and adjacent borders between the subblocks are continuous, the subblocks can be scanned according to the Z scan order among the subblocks. For example, in the decoding apparatus according to an embodiment, the coding unit 2308 can be divided into subblocks 2322, 2324, 2326, and 2328. [ At this time, subblocks 2322 and 2324 may be scanned after data processing for subblock 2330 and subblocks 2326 and 2328 may be scanned after data processing for subblock 2332 . In addition, each sub-block may be scanned according to the Z scan order.

In the above-described embodiment, scanning in accordance with the Z scan order for data units may be for data storage, data loading, data access, and the like.

In the above-described embodiments, data units can be scanned according to the Z scan order. However, the scan order of the data units may be various scan orders such as a raster scan, an N scan, a rightward diagonal scan, a horizontal scan, , And is not limited to the Z scan sequence.

In the above-described embodiments, scanning is performed on the encoding units in the reference encoding unit. However, the present invention is not limited to this, and the object of the scan may be any block in the maximum encoding unit or the processing block. have.

Also, in the above-described embodiment, it has been described that the scan is performed according to the Z scan order by dividing the block into subblocks only when there is at least one non-square block. However, in order to simplify implementation, Even if there is no block, the sub-blocks may be divided to perform the scan according to the Z scan order.

The video decoding apparatus 100 according to an exemplary embodiment generates prediction data by performing inter prediction or intra prediction on a coding unit and performs inverse conversion on a conversion unit included in the current coding unit to generate residual data And the current encoding unit can be restored by using the generated prediction data and residual data.

The prediction mode of an encoding unit according to an exemplary embodiment may be at least one of an intra mode, an inter mode, and a skip mode. According to one embodiment, the prediction mode can be selected independently for each coding unit.

If the 2Nx2N type encoding unit according to an embodiment is divided into two 2NxN or two Nx2N type encoding units, the inter mode prediction and the intra mode prediction may be separately performed for each of the 2xN type encoding units have. In addition, a skip mode may be applied to 2NxN or Nx2N type encoding units according to an embodiment.

Meanwhile, the image decoding apparatus 100 according to the embodiment may allow bi-prediction in the skip mode of 8x4 or 4x8 type encoding units. In the skip mode, since only skip mode information is transmitted for an encoding unit, the use of residual data for the encoding unit is omitted. Thus, in this case, the overhead for inverse quantization and inverse transformation can be saved. Alternatively, the image decoding apparatus 100 according to an embodiment may allow bidirectional prediction on a coding unit to which a skip mode is applied, thereby improving the decoding efficiency. In addition, the video decoding apparatus 100 according to an exemplary embodiment permits bi-directional prediction for an 8x4 or 4x8 type encoding unit. In the motion compensation step, however, the number of interpolation tapes is set relatively small, Can be used. As an example, instead of using an 8-tap interpolation filter, an interpolation filter of less than 8 taps (e.g., a 2-tap interpolation filter) may be used.

In addition, the image decoding apparatus 100 according to an exemplary embodiment divides an area included in the current encoding unit into a predetermined format (for example, slant-based partitioning), and transmits intra or inter prediction information for each divided area to signaling You may.

The image decoding apparatus 100 according to the embodiment can acquire prediction samples of the current encoding unit using the neighboring samples of the current encoding unit using the intra mode. At this time, intra prediction performs prediction using surrounding already reconstructed samples, and these samples are referred to as reference samples.

24 is a diagram illustrating reference samples for intraprediction of an encoding unit according to an embodiment. Referring to FIG. 24, for a current encoding unit 2300 having a non-rectangular block form and a horizontal length w and a vertical length h, the upper reference sample 2302 is w + h, A total of 2 (w + h) +1 reference samples are required, one for the reference sample 2304 on the left side and w + h for the left reference sample 2306 and one for the reference sample 2306 on the upper left side. For the preparation of a reference sample, padding may be performed on the portion where the reference sample does not exist, and a reference sample-by-prediction filtering process may be performed to reduce the quantization error included in the reconstructed reference sample.

Although the number of reference samples in the case where the block type of the current encoding unit is a non-rectangular shape has been described in the above embodiments, the number of reference samples is also applied to the case where the current encoding unit is a rectangular block type.

The above-described various embodiments describe operations related to the image decoding method performed by the image decoding apparatus 100. FIG. Hereinafter, the operation of the image encoding apparatus 200 for performing the image encoding method corresponding to the reverse order of the image decoding method will be described in various embodiments.

FIG. 2 illustrates a block diagram of an image encoding apparatus 200 capable of encoding an image based on at least one of block type information and division type information according to an embodiment.

The image encoding apparatus 200 may include a coding unit 220 and a bitstream generation unit 210. The encoding unit 220 may encode the input image by receiving the input image. The encoding unit 220 may encode the input image to obtain at least one syntax element. The syntax element includes a skip flag, a prediction mode, a motion vector difference, a motion vector prediction method or a transform quantized coefficient, a coded block pattern, a coded block flag, an intra prediction mode, a prediction direction, and a transform index. The encoding unit 220 can determine the context model based on the block type information including at least one of the ratio, or the size, of the shape, direction, width, and height of the encoding unit.

The bitstream generator 210 may generate a bitstream based on the encoded input image. For example, the bitstream generator 210 may generate a bitstream by entropy encoding a syntax element based on the context model. In addition, the image encoding apparatus 200 may transmit the bit stream to the video decoding apparatus 100.

According to an embodiment, the encoding unit 220 of the image encoding apparatus 200 can determine the type of an encoding unit. For example, the coding unit may have a square or a non-square shape, and information indicating this type may be included in the block type information.

According to one embodiment, the encoding unit 220 can determine what type of encoding unit is to be divided. The encoding unit 220 can determine the type of at least one encoding unit included in the encoding unit and the bitstream generating unit 210 generates a bitstream including the format information including information on the type of the encoding unit Can be generated.

According to one embodiment, the encoding unit 220 may determine whether the encoding unit is divided or not. When the encoding unit 220 determines that only one encoding unit is included in the encoding unit or that the encoding unit is not divided, the bitstream generating unit 210 includes the type information indicating that the encoding unit is not divided A bitstream can be generated. The encoding unit 220 may be divided into a plurality of encoding units included in the encoding unit, and the bitstream generating unit 210 may generate a bitstream including the division type information indicating that the encoding unit is divided into a plurality of encoding units, Can be generated.

According to an exemplary embodiment, information indicating whether to divide an encoding unit into several encoding units or which direction to be divided may be included in the division type information. For example, the division type information may indicate that division is performed in at least one of a vertical direction and a horizontal direction, or may indicate that division is not performed.

The image coding apparatus 200 determines information on the divisional mode based on the divisional mode of the encoding unit. The image coding apparatus 200 determines a context model based on at least one of a ratio or a size of a shape, a direction, a width, and a height of a coding unit. Then, the image encoding apparatus 200 generates information on the split mode for dividing the encoding unit based on the context model into a bit stream.

The image encoding apparatus 200 may obtain an arrangement for mapping at least one of the ratio, or the size, of the shape, direction, width, and height of the encoding unit to the index for the context model, in order to determine the context model. The image encoding apparatus 200 may obtain an index for the context model based on at least one of the ratio, or the size, of the shape, direction, width, and height of the encoding unit in the arrangement. The image encoding apparatus 200 can determine the context model based on the index for the context model.

In order to determine the context model, the image encoding apparatus 200 may further include a context model based on the block type information including at least one of the ratio, or the size, of the shape, direction, width, and height of the neighboring encoding units adjacent to the encoding unit You can decide. Also, the surrounding encoding unit may include at least one of a left side, a left side, an upper left side, an upper side, an upper right side, a right side, or a lower right side encoding unit of an encoding unit.

Also, in order to determine the context model, the image coding apparatus 200 can compare the length of the width of the upper peripheral encoding unit and the length of the width of the encoding unit. In addition, the image encoding apparatus 200 can compare the lengths of the heights of the left and right peripheral encoding units and the lengths of the encoding units. Also, the image encoding apparatus 200 can determine the context model based on the comparison results.

The operation of the image encoding apparatus 200 includes contents similar to the operations of the video decoding apparatus 100 described with reference to FIG. 3 to FIG. 24, and a detailed description thereof will be omitted.

25 to 38, an apparatus 2500 for decoding motion information and a method and an apparatus 2700 for encoding motion information and a method are proposed according to an embodiment.

25, the motion information decoding apparatus 2500 may include a bitstream obtaining unit 2510, an identifying unit 2530, and a decoding unit 2550.

The motion information decoding apparatus 2500 may be included in the video decoding apparatus 100 described above. For example, the bitstream obtaining unit 2510 may be included in the bitstream obtaining unit 110 of the video decoding apparatus 100 shown in FIG. 1, and the identifying unit 2530 and the decoding unit 2550 may be included in the video decoding And may be included in the decryption unit 120 of the apparatus 100.

The motion information decoding apparatus 2500 may obtain motion information for decoding the coded block through inter prediction. The type of block may be square or rectangular, and may be any geometric shape. The block according to an exemplary embodiment is not limited to a unit of a predetermined size, and may include a maximum encoding unit, an encoding unit, a prediction unit, and a conversion unit among the encoding units according to the tree structure.

In image coding and decoding, inter prediction is a prediction method that uses the similarity between the current image and another image. A reference block similar to the current block of the current image is detected from the reference image decoded prior to the current image and the distance on the coordinate between the prediction block determined from the reference block and the current block is expressed by a motion vector. In addition, the difference between pixel values between the current block and the prediction block can be represented by residual data. Instead of directly outputting the video information of the current block, it is possible to improve the efficiency of encoding and decoding by outputting an index, a motion vector, and residual data indicating a reference image derived by inter prediction of the current block.

29 is a diagram for explaining a plurality of pieces of motion information used for decoding a unidirectionally predicted block. Referring to FIG. 29, a reference image referred to by a current block is specified according to information Ref_idx indicating a reference image. In addition, a prediction candidate to be used as a predictive motion vector of a current block among prediction candidates is determined according to information (MVP_idx) indicating a predictive motion vector. The prediction candidate may be a block related to the current block or a block spatially or temporally related thereto, or a motion vector of the block. A predictive motion vector of a current block is determined according to information indicating a predictive motion vector, and a motion vector MV of a current block can be determined by a combination of a predictive motion vector and a motion vector difference (MVD).

If the reference block in the reference image is specified by the motion vector of the current block, the current block can be decoded by combining the residual data with the specified reference block (or the prediction block determined from the reference block).

29, information (Ref_idx) indicating a reference picture, information (MVP_idx) indicating a predicted motion vector, and residual motion vector (MVD) may be used as motion information for decoding a block predicted in a unidirectional manner.

30 is a diagram for explaining a plurality of pieces of motion information used for decoding a bidirectionally predicted block. 30, information (Ref_idx0) indicating a reference picture, information (MVP_idx0) indicating a predictive motion vector, and residual motion vector (MVD0) are included in list 0 for list 0 including at least one reference picture Can be used to determine the reference block in the reference image.

For the list 1 including at least one reference picture, information Ref_idx1 indicating the reference picture, information MVP_idx1 indicating the predicted motion vector, and residual motion vector MVD1 are included in the reference picture included in the list 1 Can be used to determine the block.

A prediction block can be generated by combining the reference block corresponding to the list 0 and the reference block corresponding to the list 1 and the current block can be decoded by combining the prediction block and the residual data.

30, information (Ref_idx0) indicating a reference picture related to the list 0, information MVP_idx0 indicating a predictive motion vector, and residual motion vector MVD0 are decoded in order to decode the inter-predicted blocks in both directions, Information Ref_idx1 indicating the related reference picture, information MVP_idx1 indicating the predicted motion vector, and residual motion vector MVD1 may be used as the motion information.

In a codec such as HEVC, all the motion information for decoding the inter-predicted block at the encoder side is transmitted to the decoder side, and the decoder decodes the inter-predicted block based on the received motion information. However, as the image has a high resolution, the amount of motion information to be transmitted to the decoder will increase significantly, which may be inefficient in terms of bit rate.

The present disclosure can reduce the bit rate by allowing the decoder to skip some or all of the motion information used to decode the block to the decoder and to obtain the skipped motion information directly.

Referring to FIG. 25, the bitstream obtaining unit 2510 obtains a bitstream including information for image decoding.

In one embodiment, some of the plurality of motion information used for decoding the current block may be included in the bitstream, and the remaining motion information may not be included in the bitstream.

Also, in one embodiment, not all of the plurality of motion information used for decoding the current block may be included in the bitstream.

In the present disclosure, among the plurality of motion information used for decoding the current block, motion information not included in the bitstream is referred to as omission motion information.

The motion information used for decoding the current block may include information indicating a reference image (hereinafter referred to as reference image information), information indicating a predicted motion vector (hereinafter referred to as predicted motion vector information), and residual motion vector. In one embodiment, when the motion vector of the current block is determined as a motion vector resolution selected from among several motion vector resolutions, motion vector resolution (hereinafter referred to as " motion vector resolution " (Hereinafter referred to as " MVR information ") may be further included.

When the current block is unidirectionally predicted, the number of MVR information of the current block may be one. For example, the MVR information of the current block may include an index (MVR_idx) indicating one of multiple MVRs. Also, when the current block is bi-directionally predicted, the number of MVR information of the current block may be one or two. For example, the MVR information of the current block may include an index (MVR_idx) indicating one of several MVRs or an index (MVR_idx0, MVR_idx1) indicating two. The motion vector MV0 corresponding to the list 0 can be derived according to the MVR indicated by MVR_idx0 and the motion vector MV1 corresponding to the list 1 can be derived according to the MVR indicated by MVR_idx1.

The identifying unit 2530 identifies the type of skip motion information that is not included in the bitstream, among the plurality of motion information used for decoding the current block.

In one embodiment, the identification unit 2530 may acquire motion information of a part of the plurality of pieces of motion information from the bitstream and identify motion information that is not obtained from the bitstream among the plurality of pieces of motion information as skip motion information have.

In one embodiment, if no motion information is obtained from the bitstream, the identifying unit 2530 may identify all of the plurality of motion information as skipped motion information.

In one embodiment, the identifying unit 2530 determines whether the motion information omission process has been applied to the current block, and when the motion information omission process is applied to the current block, it is determined that omission motion information exists can do. In one embodiment, when the application of the motion information omission process is confirmed, the identification unit 2530 can recognize that at least a part of the motion information of a predetermined type is not included in the bitstream. In other words, when the application of the motion information omission process is confirmed in the identification unit 2530, it can be seen that at least some of the motion information of a predetermined type should be acquired by itself in a predetermined manner.

In one embodiment, whether or not the motion information skip process has been applied to the current block includes MVR of the current block, prediction direction of the current block, information on the current block, information on the previously decoded neighboring blocks, Based on at least one of the flags indicating whether or not the application is applicable.

When it is determined whether or not the motion information skip process is applied to the current block based on at least one of MVR of the current block, prediction direction of the current block, information on the current block, and information on the previously decoded neighboring blocks, (2550) can be judged based on the same criterion as the motion information encoding apparatus 2700.

As an example, if the MVR of the current block corresponds to a predetermined MVR (for example, a resolution of a quarter pixel), the identifying unit 2530 can determine that motion information omission processing has been applied to the current block.

As an example, when the current block is predicted in both directions, the identifying unit 2530 can determine that the motion information skip process is applied to the current block.

In addition, as an example, the identification unit 2530 may determine whether or not the motion information skip processing is applied based on the information about the current block. The identification unit 2530 may compare the size of the current block with a predetermined size to determine whether or not the motion information skip process is applied. Specifically, if the horizontal or vertical size of the current block is greater than or equal to a predetermined size, it can be determined that the motion information skip process is applied to the current block.

As an example, the identification unit 2530 can determine whether to apply the motion information skip process based on information such as the size of the previously decoded neighboring block, the MVR, the prediction mode, or the prediction direction.

As an example, the identification unit 2530 can determine whether the motion information skip process is applied to the current block according to a flag obtained from the bit stream and indicating whether or not the motion information skip process is applied. For example, if the flag is equal to 1, it can be determined that the motion information skip process is applied to the current block.

In one embodiment, the identifying unit 2530 can identify the skip mode of the motion information, and identify which motion information is skipped motion information based on the skipped skipped mode that has been confirmed.

The skip mode of motion information is determined based on at least one of MVR of the current block, prediction direction of the current block, information on the current block, information on the previously decoded neighboring blocks, and index (or flag) .

In one embodiment, when the skip mode of the motion information is confirmed based on at least one of the MVR of the current block, the prediction direction of the current block, information on the current block, and information on the previously decoded neighboring blocks, 2550 can be confirmed on the same basis as the motion information encoding apparatus 2700.

At least one of the number and type of skipped motion information may be determined for each skip mode of motion information. For example, at least one of the number and types of omission motion information in the first omission mode and the number and type of omission motion information in the second omission mode can be independently determined. In one embodiment, at least one of the number and type of omission motion information may be different for each omission mode of motion information.

Figs. 31 and 32 are exemplary diagrams showing the types of skip motion information corresponding to the motion information skip mode. Fig.

31, in the case of mode 1, the skip motion information may be reference image information Ref_idx and predictive motion vector information MVP_idx, and in case of mode 2 skip motion information may be reference image information Ref_idx have. In Mode 3, the skip motion information may be reference picture information Ref_idx, predicted motion vector information MVP_idx, and residual motion vector MVD.

Referring to FIG. 32, in the mode 1, there is no omitted motion information. In the mode 2, the skipped motion information may be the residual motion vector MVD0 corresponding to the list 0, and in the case of the mode 3, May be the residual motion vector MVD1 corresponding to the list 1.

At least one of the types and the number of skipped motion information corresponding to the motion information skip mode may be individually determined for each of the case where the current block is unidirectionally predicted and the case where the current block is bidirectionally predicted. For example, when the current block is unidirectionally predicted, the skip motion information corresponding to the mode 1 may be reference image information, and when the current block is bidirectionally predicted, the skip motion information corresponding to the mode 1 corresponds to the lease 0 May be the reference motion picture information and the residual motion vector corresponding to the list 0. In other words, the identifying unit 2530 can identify the prediction direction and the motion information skip mode of the current block, and identify the skip motion information type based on the confirmed prediction direction and the skip motion information skip mode.

The number of modes shown in FIGS. 31 and 32 and the number and types of omitted motion information corresponding to each mode are only examples, and the number of modes and the number of omitted motion information corresponding to each mode And the type may be variously changed.

As described above, the identifying unit 2530 can identify the skipped mode of the motion information and identify the skipped motion information type based on the skipped skipped mode.

As an example, the identifying unit 2530 can check the skip mode of the motion information based on the MVR of the current block. For example, when the MVR of the current block is a resolution of a quarter-pixel unit, the first mode is determined, and when the MVR of the current block is a resolution of a half-pixel unit, the second mode can be determined.

In addition, as an example, the identifying unit 2530 determines whether the current block is predicted by referring to the reference image in list 0 (i.e., unidirectional prediction), whether the current block is predicted with reference to the reference image in list 1 ), The skip mode may be determined according to whether the current block is predicted by referring to the reference image in list 0 and the reference image in list 1 (i.e., bidirectional prediction). For example, when the current block refers to the reference image in the list 0, the first mode is selected. When the current block refers to the reference image in the list 1, the second mode is selected. When the reference image is referred to, the third mode can be determined.

In addition, as an example, the identification unit 2530 may determine the skip mode of the motion information based on the information about the current block. For example, the skip mode of the motion information may be determined by comparing the size of the current block with a predetermined size. Specifically, if the horizontal size or the vertical size of the current block is greater than or equal to the preset size, the second mode can be determined to be the first mode, and the horizontal size or the vertical size of the current block is less than the predetermined size.

In addition, as an example, the identification unit 2530 may determine an omission mode of the motion information based on the information on the previously decoded neighboring blocks. For example, the skip mode of the motion information can be determined based on information such as the size of the previously decoded neighboring block, the MVR, the prediction mode, or the prediction direction.

As an example, the identifying unit 2530 may obtain an index (or a flag) indicating a skipped mode from the bitstream and determine an abbreviated mode according to the obtained index (or flag). For example, if the obtained index corresponds to 0, it can be determined as mode 1, mode 2 corresponding to index 1, and mode 3 corresponding to index 2.

When the type of the omitted motion information is identified by the identifying unit 2530, the decoding unit 2550 acquires the skipped motion information based on the predetermined method. The decoding unit 2550 can decode the current block using the skip motion information and a plurality of motion information including motion information obtainable from the bitstream.

As described above, the plurality of motion information may include reference image information, predictive motion vector information, and residual motion vector. The decoding unit 2550 obtains a motion vector of the current block by adding the predicted motion vector and the residual motion vector, and searches for a reference block in the reference image based on the motion vector. The decoding unit 2550 reconstructs the current block in the spatial domain by adding the inverse quantized and inverse transformed residual data to the reference block (or the prediction block). The image including the restored current block is filtered, and the filtered image can be used as a reference image of the next image.

Hereinafter, a method for the decoding unit 2550 to acquire omitted motion information will be described in detail.

In one embodiment, the decoding unit 2550 may obtain skip motion information using motion information of at least one candidate block spatially or temporally related to the current block.

FIG. 33 shows candidate blocks spatially or temporally related to the current block. The candidate block may be a block decoded before the current block, and the spatial block may include at least one block spatially adjacent to the current block. In addition, the temporal block may include at least one block located at the same point as the current block in the reference image having a POC different from the POC (Picture Order Count) of the current block, and a block spatially adjacent to the block at the same position .

33, a spatial block spatially related to the current block 3300 is divided into a left lower block A, a left lower block B, a right upper end block C, an upper right block D, And an upper left outer block (E). A temporally related temporal block with respect to the current block 3300 includes a co-located block F belonging to a reference picture having a different POC from the current block 3300 and a neighboring block G of co-located block F . The candidate block shown in FIG. 33 is one example, and in one embodiment, at least one candidate block used to acquire skipped motion information includes only spatial blocks spatially related to the current block, But may include only relevant temporal blocks.

In one embodiment, the decoding unit 2550 determines whether motion information exists in a plurality of candidate blocks spatially or temporally related to the current block according to a predetermined priority, The skip motion information can be obtained based on the motion information of the block. As an example, if priority is set from the A block to the G block, the decoding unit 2550 sequentially searches for a candidate block in which motion information exists from the A block to the G block. The skip motion information can be obtained by using the motion information of the candidate block in which the existence of motion information is confirmed first. For example, when the type of the skip motion information is the reference image information and the predictive motion vector information, the decoding unit 2550 decodes the motion information of the candidate block in which the presence of the motion information is first identified, specifically, It is possible to confirm the motion vector information and determine the confirmed information as the skip motion information.

Also, in one embodiment, the decoding unit 2550 may acquire skip motion information by combining motion information of a plurality of candidate blocks having motion information among a plurality of candidate blocks spatially or temporally related to the current block. For example, the decoding unit 2550 may combine the motion information of a plurality of candidate blocks having motion information according to a predetermined equation, and obtain the combined result value as skipped motion information. The predetermined equation may include an equation for deriving an average value, an intermediate value, and the like. For example, when Ref_idx of the A block is 1 and Ref_idx of the B block is 3 when the type of the omitted motion information is the reference image information (Ref_idx), 2, which is an average value of the two, is set as reference image information of the current block Can be obtained. Among the motion information, reference picture information and predictive motion vector information can be represented by integer values. If the result value derived through the predetermined formula is not an integer unit, the result value is increased, decreased, or rounded to obtain omission motion information You may. For example, when the Ref_idx of the A block is 1 and the Ref_idx of the B block is 2, the rounded 2 at the average value of 1.5 can be determined as the reference image information Ref_idx of the current block.

In one embodiment, the decoding unit 2550 may determine skip motion information based on preset basic motion information. In one embodiment, the decoding unit 2550 can set basic motion information on a picture basis, a slice basis, or a block basis. Alternatively, the decoding unit 2550 may acquire basic motion information from the bitstream in picture units, slice units, or block units.

The decoding unit 2550 can use the basic motion information to acquire the skip motion information. For example, Ref_idx may be set to 0, MVP_idx may be set to 0, and MVD may be set to 0 as basic motion information. When the type of skip motion information is Ref_idx and MVP_idx, the decoding unit 2550 can determine the value of Ref_idx and MVP_idx of the current block to be 0. [ The value set as the basic motion information can be variously changed within the self-defined range.

Also, in one embodiment, the decoding unit 2550 may acquire omitted motion information based on the motion information derived through the decoder side MV derivation (DMVD). DMVD is a technology for directly deriving motion information from the decoder side, not by including the motion information explicitly in the bitstream to enable the decoder to acquire it, and by using template matching or bilateral template matching It is a technique to derive the motion information of the current block. Template matching is a method of using a correlation between pixels of blocks adjacent to a prediction target block and pixels in already decoded reference images.

In one embodiment, when there are a plurality of schemes for acquiring skipped motion information, the decoding unit 2550 may acquire skipped motion information using at least one scheme. In one embodiment, based on the type of omitted motion information to be acquired, the corresponding method can be selected, and skip motion information can be obtained according to the selected method. For example, if the skip motion information to be acquired is reference image information, the skip motion information is a first scheme, the skip motion information is predictive motion vector information, and the skip motion information is a residual motion vector. . ≪ / RTI >

Further, in one embodiment, when there are a plurality of pieces of omitted motion information to be acquired, the decoding unit 2550 may acquire each of the plurality of omitted motion information in different ways.

In one example, a method of acquiring skipped motion information based on the motion information of the candidate block described above is referred to as a first method, a method of acquiring skipped motion information based on basic motion information is referred to as a second method, When the method for acquiring the skip motion information based on the motion information determined by the motion information decoding method is the third scheme, each of the plurality of skip motion information may be obtained in different ways among the first scheme, the second scheme, and the third scheme. For example, the reference picture information may be determined in a first mode, the predictive motion vector information may be determined in a second mode, and the residual motion vector may be determined in a third mode.

FIG. 34 shows an exemplary syntax for acquiring skipped motion information according to a motion information skip mode for a bidirectionally predicted block.

34, if it is confirmed that the current block is bi-directionally predicted, it is determined that the motion information skip process is applied to the current block, the type of skip motion information is identified according to bi-directional prediction type information bi_type_idx, Shows a procedure for acquiring omitted motion information according to a predetermined method.

Referring to FIG. 34, bi_type_idx is extracted when the current block is bidirectionally predicted in a syntax. If the current block is bi-directionally predicted, it can be determined that the motion information skip process is applied to the current block.

bi_type_idx is an index indicating an abbreviation mode. If bi_type_idx is equal to 0, the abbreviation mode is confirmed as a mode 1. b, the residual motion vector MVD and the reference picture index corresponding to the list 0 in the mode 1 and the residual motion vector and the reference picture index corresponding to the list 1 are parsed, that is, . The predictive motion vector corresponding to the list 0 and the predictive motion vector corresponding to the list 1 are identified as omitted motion information. The predictive motion vector corresponding to the list 0 and the predictive motion vector corresponding to the list 1 can be determined according to a predetermined method.

If bi_type_idx is equal to 1, the skip mode is confirmed as mode 2. Referring to the c syntax, only residual motion vectors corresponding to list 1 in mode 2 are parsed. The residual motion vector, the reference picture index and the predicted motion vector corresponding to the list 0, the reference picture index corresponding to the list 1, and the predictive motion vector are determined as the omitted motion information. The predicted motion vector and the reference picture index corresponding to the list 0 and the predicted motion vector and the reference picture index corresponding to the list 1 can be determined according to a predetermined method. In mode 2, the residual motion vector corresponding to list 0 can be determined to be a preset value of 0 (or zero vector). Therefore, the predicted motion vector corresponding to the list 0 can be the motion vector MV0 of the current block. According to the embodiment, in mode 2, at least one of the reference picture index corresponding to the list 0 and the reference picture index corresponding to the list 1 may be parsed from the bit stream instead of being determined as the omitted motion information.

According to one embodiment, in mode 2, the residual motion vector corresponding to the list 0 may be regarded as not included in the plurality of motion information used for decoding the current block. Therefore, even if the residual motion vector corresponding to the list 0 is not obtainable from the bitstream, the decoding unit 2550 does not identify the residual motion vector corresponding to the list 0 as skipped motion information, The reference block can be searched using only the predicted motion vector.

If bi_type_idx is equal to 2, the skip mode is confirmed as mode 3. Referring to the syntax d, only residual motion vectors corresponding to list 0 in mode 3 are parsed. The reference picture index and the predicted motion vector corresponding to the list 0, the reference picture index corresponding to the list 1, the predicted motion vector and the residual motion vector are determined as skipped motion information. The predicted motion vector and the reference picture index corresponding to the list 0 and the predicted motion vector and the reference picture index corresponding to the list 1 can be determined according to a predetermined method. In mode 3, the residual motion vector corresponding to list 1 may be determined to be a preset value of 0 (or zero vector). Therefore, the predicted motion vector corresponding to the list 1 can be the motion vector MV1 of the current block. According to the embodiment, in mode 3, at least one of the reference video index corresponding to the list 0 and the reference video index corresponding to the list 1 may be parsed from the bit stream instead of being determined as the omitted motion information.

According to one embodiment, in mode 3, the residual motion vector corresponding to the list 1 may be regarded as not included in the plurality of motion information used for decoding the current block. Therefore, even if the residual motion vector corresponding to the list 1 is not obtainable from the bitstream, the decoding unit 2550 does not identify the residual motion vector corresponding to the list 1 as skipped motion information, The reference block can be searched using only the predicted motion vector.

In one embodiment, when the MVR of the current block is included in the motion information used for decoding the current block, the bitstream obtaining unit 2510 may obtain information indicating the MVR of the current block from the bitstream.

35 is a diagram showing a syntax for obtaining information on MVR from a bitstream.

Referring to FIG. 35, if the slice including the current encoding unit in the a syntax is not an I-slice, cu_skip_flag is extracted in the b syntax. cu_skip_flag indicates whether skip mode is applied to the current encoding unit. When the application of the skip mode is confirmed in the c syntax, the current encoding unit is processed according to the skip mode. If the skip mode is not found in the d statement, the pred_mode_flag is extracted from the e statement. pred_mode_flag indicates whether the current coding unit is intra-predicted or inter-predicted. If the current encoding unit is not intrapredicted in the f-syntax, that is, if it is inter-predicted, pred_mvr_idx is extracted from the g-syntax. pred_mvr_idx is the index indicating the MVR of the current coding unit, and the MVR corresponding to each index may be as shown in Table 2 below.

MVR Index 0 One 2 3 4 Resolution (R) in pel 1/4 1/2 One 2 4

The MVR of the current block may indicate the precision of the position of the pixel that the motion vector of the current block among the pixels included in the reference image (or the interpolated reference image) can point to. The MVR of the current block may be selected from at least one candidate MVR. The at least one candidate MVR may be, for example, MVR in units of 1/8 pixel, MVR in quarter pixel, MVR in 1/2 pixel, MVR in 1 pixel, MVR in 2 pixels, MVR, and MVR of 8-pixel units. However, the present invention is not limited thereto.

In one embodiment, the bitstream obtaining unit 2510 may obtain information on the MVR of the current block from the bitstream on a block-by-block, slice-by-block, or picture-by-block basis. In one embodiment, when the MVR information of the current block is identified as skipped motion information, the decoding unit 2550 may determine the MVR of the current block according to a predetermined method.

In one embodiment, the decoding unit 2550 may adjust the predicted motion vector and / or the residual motion vector when the motion vector of the current block is determined according to a predetermined MVR. Adjusting the predictive motion vector and / or the residual motion vector of the current block may mean that the position of a pixel indicated by the predicted motion vector and / or the residual motion vector of the current block is changed corresponding to the MVR of the current block. A method of adjusting the predictive motion vector and / or the residual motion vector of the current block will be described later with reference to FIG. 36 to FIG.

26 is a flowchart for explaining a motion information decoding method according to an embodiment.

In step S2610, the motion information decoding apparatus 2500 identifies the type of skip motion information that is not included in the bitstream, among the plurality of motion information used for decoding the inter-predicted current block.

In one embodiment, when the motion information decoding apparatus 2500 determines that the motion information skip processing is applied to the current block, it can recognize that the skip motion information exists. The motion information decoding apparatus 2500 can identify the motion information skip mode and identify the skip motion information type based on the confirmed skip motion information skip mode.

In step S2620, the motion information decoding apparatus 2500 can acquire omitted motion information based on a predetermined method.

In one example, the motion information decoding apparatus 2500 may obtain skip motion information based on motion information of at least one candidate block.

In one example, the motion information decoding apparatus 2500 may obtain skip motion information based on preset basic motion information.

In addition, in one example, the motion information decoding apparatus 2500 may acquire omitted motion information based on the motion information acquired through the DMVD technique.

Since the method of acquiring omitted motion information has been described in detail in the foregoing, a detailed description thereof will be omitted.

The motion information decoding apparatus 2500 can obtain motion information other than omitted motion information from a plurality of pieces of motion information from a bitstream.

In step S2630, the motion information decoding apparatus 2500 decodes the current block based on the plurality of motion information including the obtained skip motion information.

27 is a block diagram showing a configuration of a motion information encoding apparatus 2700 according to an embodiment.

Referring to FIG. 27, the motion information encoding apparatus 2700 according to an embodiment may include a determination unit 2710, an encoding unit 2730, and a bitstream generation unit 2750. The motion information encoding apparatus 2700 may be included in the image encoding apparatus 200 described above. For example, the determination unit 2710 and the encoding unit 2730 of the motion information encoding apparatus 2700 may be included in the encoding unit 220 of the image encoding apparatus 200, and the bits of the motion information encoding apparatus 2700 The stream generation unit 2750 may be included in the bitstream generation unit 210 of the image encoding apparatus 200.

The determination unit 2710 determines the type of omission motion information to be omitted from the bitstream, among the plurality of motion information used for decoding the current block to be inter-predicted.

As described above, the plurality of motion information used for decoding the current block may include reference image information, predictive motion vector information, and residual motion vector, and may further include MVR information of the current block according to an embodiment .

The determination unit 2710 can determine whether to apply the motion information skip processing to the current block before deciding to omit motion information of some or all of the plurality of motion information.

In one embodiment, the determination unit 2710 may determine whether to apply the motion information skip processing according to a predetermined criterion.

In one embodiment, the determination unit 2710 determines whether or not to apply the motion information skip processing to at least one of MVR of the current block, prediction direction of the current block, information on the current block, and information on the previously encoded neighboring blocks Can be judged on the basis of.

In one embodiment, the determination unit 2710 determines whether or not the motion information skip processing is applied in consideration of the case where the information indicating whether the motion information skip processing is applied is not transmitted to the motion information decoding apparatus 2500, (2500).

As an example, if the MVR of the current block corresponds to a predetermined MVR (for example, a resolution of a quarter pixel), the determination unit 2710 can determine to apply the motion information skip processing to the current block.

As an example, when the current block is predicted in both directions, the determination unit 2710 may determine to apply the motion information skip processing to the current block.

As an example, the determination unit 2710 may determine whether to apply the motion information skip processing based on the information about the current block. The determination unit 2710 may compare the size of the current block with a predetermined size to determine whether or not the motion information skip process is applied.

As an example, the determination unit 2710 can determine whether to apply the motion information skip processing based on information such as the size of the previously decoded neighboring block, the MVR, the prediction mode, or the prediction direction.

In one embodiment, the determination unit 2710 may determine a motion information skip mode for the current block, and determine the type of skip motion information that is not included in the bitstream, based on the skipped motion information skip mode.

In one embodiment, the determination unit 2710 may determine the skip mode of the motion information according to a predetermined criterion.

In one embodiment, the determination unit 2710 determines the skip mode of the motion information based on at least one of MVR of the current block, prediction direction of the current block, information on the current block, and information on the previously encoded neighboring blocks .

The decision unit 2710 decides the motion information skip mode to be the same as the motion information decoding apparatus 2500 in consideration of the case in which the information indicating the motion information skip mode is not transmitted to the motion information decoding apparatus 2500 .

At least one of the number and type of skipped motion information may be determined for each skip mode of motion information. For example, at least one of the number and kind of omission motion information in the first omission mode and the number and type of omission motion information in the second omission mode can be individually determined. At least one of the number and type of omission motion information may be different for each omitting mode.

The type of skipped motion information corresponding to the motion skip information mode may be determined separately for the case where the current block is unidirectionally predicted and the case where the current block is bidirectionally predicted.

In one embodiment, the determination unit 2710 can determine the skip mode of the motion information based on the MVR of the current block. For example, when the MVR of the current block is a resolution of a quarter-pixel unit, the first mode is determined, and when the MVR of the current block is a resolution of a half-pixel unit, the second mode can be determined.

Further, in one embodiment, the determination unit 2710 determines whether the current block refers to the reference image in list 0 (i.e., unidirectional prediction), whether the current block refers to the reference image in list 1 The skip mode may be determined based on whether the block refers to the reference image in list 0 and the reference image in list 1 (i.e., bidirectional prediction).

Further, in one embodiment, the determination unit 2710 may determine the skip mode of the motion information based on the information about the current block. For example, the skip mode of the motion information may be determined by comparing the size of the current block with a predetermined size. Specifically, if the horizontal size or the vertical size of the current block is greater than or equal to the preset size, the second mode can be determined to be the first mode, and the horizontal size or the vertical size of the current block is less than the predetermined size.

Further, in one embodiment, the determination unit 2710 may determine an omission mode of the motion information based on information on the previously decoded neighboring blocks. For example, the skip mode of the motion information can be determined based on information such as the size of the previously decoded neighboring block, the MVR, the prediction mode, or the prediction direction.

When the type of skipped motion information is determined by the determination unit 2710, the encoding unit 2730 acquires skipped motion information based on a predetermined method.

In one embodiment, the encoding unit 2730 can obtain skip motion information using motion information of at least one candidate block spatially or temporally related to the current block.

In one embodiment, the encoding unit 2730 determines whether motion information exists in a plurality of candidate blocks spatially or temporally related to the current block according to a predetermined priority, The skip motion information can be obtained based on the motion information of the block.

Also, in one embodiment, the encoding unit 2730 may acquire skip motion information by combining motion information of a plurality of candidate blocks having motion information among a plurality of candidate blocks spatially or temporally related to the current block. For example, the encoding unit 2730 may combine the motion information of a plurality of candidate blocks having motion information according to a predetermined equation, and obtain the combined result value as skipped motion information. The predetermined equation may include an equation for deriving an average value, an intermediate value, and the like.

In one embodiment, the encoding unit 2730 may determine skip motion information based on the basic motion information. Basic motion information may be preset in the encoding unit 2730. [ In one embodiment, the encoding unit 2730 may set basic motion information on a picture basis, a slice basis, or a block basis. In one embodiment, the bitstream generator 2750 may include basic motion information determined in units of pictures, slices, or blocks in the bitstream.

Also, in one embodiment, the encoding unit 2730 may acquire omitted motion information based on the motion information derived through the DMVD (decoder side MV derivation).

In one embodiment, when there are a plurality of schemes for acquiring skipped motion information, the encoding unit 2730 may acquire skipped motion information using at least one scheme. In one embodiment, based on the type of omitted motion information to be acquired, the corresponding method can be selected, and skip motion information can be obtained according to the selected method. For example, if the skip motion information to be acquired is reference image information, the skip motion information is a first scheme, the skip motion information is predictive motion vector information, and the skip motion information is a residual motion vector. . ≪ / RTI >

Further, in one embodiment, when there are a plurality of pieces of omitted motion information to be acquired, the encoding unit 2730 may acquire each of the plurality of omitted motion information in different ways.

Also, the encoding unit 2730 can determine the remaining motion information based on the obtained skip motion information. As an example, the encoding unit 2730 can determine the remaining motion information on a cost basis. A rate-distortion cost may be used.

For example, when the skip motion information includes reference image information, a reference image referred to by a current block is specified according to reference image information determined based on a predetermined scheme, and a prediction motion of at least one prediction candidate It is possible to select a prediction candidate to be used as a vector. The encoding unit 2730 may determine a distance based on the coordinate between the reference block found in the reference image and the current block as a motion vector and determine a difference between the motion vector of the current block and the predicted motion vector as a residual motion vector.

Also, for example, when the skip motion information includes predictive motion vector information, the encoding unit 2730 acquires a predicted motion vector based on a predetermined scheme, and determines a current block based on the cost among the previously encoded images One or more reference images are determined. The encoding unit 2730 may determine a motion vector based on the determined reference image and determine a difference between a motion vector of the current block and a predictive motion vector obtained according to a predetermined method as a residual motion vector.

Also, for example, when omitted motion information includes a residual motion vector, the coding unit 2730 determines a residual motion vector based on a predetermined method. As an example, the residual motion vector may be determined as a zero vector. The encoding unit 2730 determines a reference image of the current block based on the cost, adds the residual motion vectors determined according to the predetermined scheme and the respective prediction candidates, and derives motion vectors corresponding to the respective prediction candidates. The encoding unit 2730 may determine any one motion vector based on the cost among the motion vectors and determine a prediction candidate corresponding to the determined motion vector as a predicted motion vector.

For example, when omitted motion information includes MVR information, the encoding unit 2730 acquires the MVR of the current block based on a predetermined method, and generates a reference image, a predicted motion vector, and a residual motion vector .

In one embodiment, when the current block is bidirectionally predicted, the encoding unit 2730 may determine that the motion information skip process is applied to the current block, and determine the skip mode of mode 1, mode 2, or mode 3.

In the example, when the motion information skip mode is mode 1, the encoding unit 2730 encodes the residual motion vector and the reference image index corresponding to the list 0, the residual motion vector corresponding to the list 1, And determines the predicted motion vector corresponding to the list 0 and the predictive motion vector corresponding to the list 1 as the skip motion information. The predictive motion vector corresponding to the list 0 and the predictive motion vector corresponding to the list 1 can be determined according to a predetermined method.

In one example, if the motion information skip mode is mode 2, the encoding unit 2730 can determine the residual motion vector corresponding to the list 1 as motion information to be included in the bitstream. The encoding unit 2730 can determine the residual motion vector, the reference picture index, and the predicted motion vector corresponding to the list 0, the reference picture index corresponding to the list 1, and the predicted motion vector as skipped motion information. The predicted motion vector and the reference picture index corresponding to the list 0 and the predicted motion vector and the reference picture index corresponding to the list 1 can be determined according to a predetermined method. In mode 2, the residual motion vector corresponding to list 0 can be determined to be a preset value of 0 (or zero vector). According to the embodiment, in mode 2, the residual motion vector corresponding to the list 0 may be regarded as not included in the plurality of motion information used for decoding the current block. Therefore, the coding unit 2730 may not separately acquire the residual motion vector even if the residual motion vector corresponding to the list 0 is not included in the bitstream.

In one example, when the motion information skip mode is mode 3, the encoding unit 2730 can determine the residual motion vector corresponding to the list 0 as motion information to be included in the bitstream. The encoding unit 2730 can determine the reference video index and the predicted motion vector corresponding to the list 0, the reference video index corresponding to the list 1, the predicted motion vector, and the residual motion vector as skipped motion information. The predicted motion vector and the reference picture index corresponding to the list 0 and the predicted motion vector and the reference picture index corresponding to the list 1 can be obtained according to a predetermined method. In mode 3, the residual motion vector corresponding to list 1 may be determined to be a preset value of 0 (or zero vector). According to one embodiment, in mode 3, the residual motion vector corresponding to the list 1 may be regarded as not included in the plurality of motion information used for decoding the current block. Therefore, the encoding unit 2730 may not separately acquire the residual motion vector even if the residual motion vector corresponding to the list 1 is not included in the bitstream.

The bitstream generator 2750 generates a bitstream including information related to the current block encoded according to the inter prediction.

In one embodiment, the bitstream may include at least one of information indicating whether motion information skip processing is applied, information indicating a motion information skip mode, and motion information other than skip motion information in a plurality of motion information.

In addition, the bitstream may further include information indicating the MVR of the current block, which is one of the motion information. The bitstream including the information indicating the MVR may have a structure like the syntax shown in FIG.

In an embodiment, the encoding unit 2730 may adjust the predicted motion vector and / or the residual motion vector when the motion vector of the current block is determined according to a predetermined MVR. Adjusting the predictive motion vector and / or the residual motion vector of the current block may mean that the position of a pixel indicated by the predicted motion vector and / or the residual motion vector of the current block is changed corresponding to the MVR of the current block. A method of adjusting the predictive motion vector and / or the residual motion vector of the current block will be described later with reference to FIG. 36 to FIG.

28 is a flowchart for explaining a motion information encoding method according to an embodiment.

In step S2810, the motion information encoding apparatus 2700 determines the type of skip motion information that is not included in the bitstream, among the plurality of motion information used for decoding the current block.

In one embodiment, the motion information encoding device 2700 can first determine whether to apply the motion information skip processing to the current block.

In one embodiment, the motion information encoding apparatus 2700 may determine the motion information skip mode and determine the type of skip motion information that is not included in the bitstream according to the determined skip mode.

In one embodiment, the motion information encoding apparatus 2700 may first determine the type of skip motion information not to be included in the bitstream, and determine a skip motion information skipping mode corresponding to the determined skip motion information.

In step S2820, the motion information encoding device 2700 acquires skipped motion information based on a predetermined method.

In one example, the motion information encoding apparatus 2700 may acquire skip motion information based on motion information of at least one candidate block.

In one example, the motion information encoding device 2700 may acquire skipped motion information based on preset basic motion information.

In addition, in one example, the motion information encoding apparatus 2700 may acquire skip motion information based on the motion information acquired through the DMVD technique.

Since the method of acquiring omitted motion information has been described in detail in the foregoing, a detailed description thereof will be omitted.

The motion information encoding apparatus 2700 can acquire motion information other than skip motion information among a plurality of motion information based on a cost.

In step S2830, the motion information encoding apparatus 2700 generates a bitstream including motion information other than skip motion information.

In one embodiment, the bitstream may further include at least one of information indicating whether motion information omission processing is applied or information indicating a motion information omission mode.

Hereinafter, a method of adjusting the predicted motion vector and / or the residual motion vector when the MVR is determined for the current block and the motion vector is determined according to the MVR will be described.

The motion information encoding device 2700 and the motion information decoding device 2500 may determine any one candidate MVR among the at least one candidate MVR that can be selected for the current block to be the MVR of the current block. The motion information decoding apparatus 2500 may determine the MVR of the current block based on the MVR information obtained from the bit stream. If the MVR of the current block is determined, the predicted motion vector and / or the residual motion vector should be adjusted according to the MVR of the current block.

36 shows a case where a minimum MVR selectable for a current block is a quarter-pixel unit MVR, a motion vector corresponding to a 1/4 pixel unit MVR, a 1/2 pixel unit MVR, a 1 pixel unit MVR, and a 2 pixel unit MVR Indicates the positions of the pixels that can be pointed.

36 (a), 36 (b), 36 (c), and 36 (d) respectively show MVR on a quarter-pixel basis, MVR on a half-pixel basis, MVR on a pixel- (Denoted by a black square) of the pixels that the motion vector of the unit MVR can point to.

When the minimum MVR is a quarter-pixel-unit MVR, the coordinates of a pixel that a motion vector of a quarter-pixel-unit MVR can point to are (a / 4, b / 4) (2c / 4, 2d / 4) (c, d is an integer), and the coordinates of a pixel that a motion vector of one pixel unit MVR can point to is 4e / 4, 4f / 4) (e, f is an integer), and the coordinates of the pixel that the motion vector of the 2-pixel-unit MVR can point to are (8g / 4, 8h / 4) do. That is, when the minimum MVR is 2 ^m (m is an integer) pixel unit, the coordinates of the pixel that can be represented by 2 ⁿ (n is an integer) pixel unit MVR is (2 ^nm * i / 2 ^-m , 2 ^nm * j / 2 ^-m ) (i, j is an integer). Even if the motion vector is determined according to the specific MVR, the motion vector is expressed by the coordinates in the interpolated image according to the unit of the 1/4 pixel which is the minimum MVR.

In one embodiment, the motion information encoding apparatus 2700 determines a motion vector in an interpolated image according to a minimum MVR. Therefore, a motion vector may be represented by a reciprocal of a pixel unit value of a minimum MVR, For example, if the minimum MVR is 2 ^m (m is an integer) pixel unit, it can be multiplied by 2 ^-m to represent a motion vector in an integer unit. 2 ^-m may be used in the motion information coding apparatus 2700 and the motion information decoding apparatus 2500. [

If the motion vector of the 1/2 pixel unit MVR starting from the coordinate (0, 0) indicates the coordinates (2/4, 6/4) and the minimum MVR has the quarter pixel unit, (2, 6), which is a value obtained by multiplying the motion vector by the integer 4, can be determined as a motion vector.

The motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 can adjust the predicted motion vector of the current block if the MVR of the current block is larger than the minimum MVR of the selectable candidate MVR. The fact that the MVR of the current block is larger than the minimum MVR may mean that the pixel unit of the MVR of the current block is larger than the pixel unit of the minimum MVR. For example, the MVR of one pixel unit is larger than that of the half-pixel unit, and the MVR of the half-pixel unit is larger than that of the quarter-pixel unit.

The motion information encoding device 2700 and the motion information decoding device 2500 may adjust the predicted motion vector represented by the coordinates in the interpolated image according to the minimum MVR to the MVR of the current block, Instead, it can be adjusted to point to surrounding pixels.

37, in order to adjust the predicted motion vector A pointing to the pixel 3710 of the coordinates (19, 27) on the basis of the coordinate (0, 0) to the MVR of the current block by one pixel unit MVR The coordinates (19, 27) of the pixel 3710 indicated by the predicted motion vector A are divided by the integer 4 (i.e., downscale), and the coordinates (19/4, 27/4) The unit may not be indicated.

The motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 can adjust the downscaled predicted motion vector to point to an integer pixel unit. For example, the coordinates of the surrounding integer pixels around the coordinates (19/4, 27/4) are (16/4, 28/4), (16/4, 24/4), (20/4 , 28/4), (20/4, 24/4). At this time, the motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 are arranged such that the downscaled predicted motion vector A is the coordinates (20 / 4, 28/4) and then multiplied again by an integer 4 (i.e., upscaled) to determine whether the finally adjusted predicted motion vector D is a pixel 3740 corresponding to the coordinates 20, 28 ). ≪ / RTI >

In one embodiment, the motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 may be configured such that the downscaled predicted motion vector is located at a left-bottom position, a left-top position or a right-bottom position The coordinates may be adjusted to indicate the coordinates.

In one embodiment, when either the x-coordinate value or the y-coordinate value indicated by the downscaled predictive motion vector corresponds to an integer, only the coordinate value that does not correspond to the integer is increased or decreased so that the adjusted coordinate value It can be made to correspond to an integer. That is, when only the x-coordinate value indicated by the downscaled predictive motion vector corresponds to an integer, the adjusted predictive motion vector is an integer pixel located at the upper end of the pixel indicated by the predictive motion vector before being adjusted or an integer pixel located at the lower end . ≪ / RTI > Alternatively, when only the y coordinate value indicated by the downscaled predictive motion vector corresponds to an integer, the adjusted predictive motion vector is an integer pixel located on the left side of the pixel indicated by the predictive motion vector before the adjustment, or an integer pixel located on the right side . ≪ / RTI >

The motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 may select a point indicated by the adjusted predictive motion vector differently according to the MVR of the current block when adjusting the predicted motion vector.

38, if the MVR of the current block is a half-pixel unit MVR, the adjusted predicted motion vector is a left-upper pixel 3830 of the pixel indicated by the predicted motion vector before being adjusted, And if the MVR of the current block is MVR per pixel, the adjusted predictive motion vector indicates the right-top pixel 3820 of the pixel indicated by the predicted motion vector before being adjusted, and if the MVR of the current block is 2 In the case of pixel-based MVR, the adjusted predicted motion vector can be adjusted to point to the right-bottom pixel 3840 of the pixel indicated by the predicted motion vector before being adjusted.

The process of adjusting the predicted motion vector described with reference to FIGS. 37 and 38 can be similarly applied to the process of adjusting the residual motion vector. When the residual motion vector is determined to be skipped motion information and derived according to a predetermined scheme in the motion information encoding apparatus 2700 and the motion information decoding apparatus 2500, the derived residual motion vector is interpolated with the minimum MVR like the predicted motion vector And the precision of the residual motion vector is made to correspond to the precision of the motion vector of the current block.

The motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 can adjust the predicted motion vector according to the following equation 1 when the predicted motion vector is adjusted in consideration of the MVR and the minimum MVR of the current block.

[Equation 1]

MVP '= ((MVP >> k) + offset) << k

In Equation (1), MVP 'denotes an adjusted predicted motion vector, k is a value determined according to the difference between MVR and MVR of the current block, MVR of the current block is 2 ^m pixel units (m is an integer) Is a unit of 2 ⁿ pixels (n is an integer), and when m> n, k can be mn. In one embodiment, k may be an index of the MVR. When the candidate MVR includes a quarter pixel unit MVR, a half pixel unit MVR, a one pixel unit MVR, a two pixel unit MVR, and a four pixel unit MVR, The MVR corresponding to each index is shown in Table 2. When the MVR index is received from the bitstream, the motion information decoding apparatus 2500 can adjust the predicted motion vector according to Equation (1) using the MVR index as k.

In Equation (1), &quot; or &quot; denotes a bit shift operation, which means an operation for reducing or increasing the size of a predicted motion vector. Also, offset means a value to be added or subtracted to indicate an integer pixel when the downscaled predicted motion vector does not point to an integer pixel according to the value of k. offset may be determined differently for each of the x-coordinate value and the y-coordinate value of the predicted motion vector.

In the case of adjusting the residual motion vector as described above, Equation (1) can be changed to Equation (1-1) below.

[Mathematical expression 1-1]

MVD '= ((MVD >> k) + offset) << k

In Equation (1), MVD 'denotes an adjusted residual motion vector, and MVD denotes a residual motion vector obtained according to a predetermined method.

In one embodiment, when the downscaled predicted motion vector (or residual motion vector) is changed to point to an integer pixel, the motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 may change .

In one embodiment, when the x and y coordinate values of the downscaled predicted motion vector (or residual motion vector) do not point to integer pixels, the x coordinate value of the downscaled predicted motion vector (or residual motion vector) And the y coordinate value may be always increased to point to an integer pixel, and may be always reduced to point to an integer pixel. Alternatively, the x-coordinate value and y-coordinate value of the downscaled predicted motion vector (or residual motion vector) may be rounded to indicate an integer pixel.

The motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 may calculate the downscale and upscale of the predicted motion vector (or residual motion vector) when adjusting the predicted motion vector (or residual motion vector) And may be adjusted in the coordinate plane in the reference image interpolated according to the minimum MVR such that the predicted motion vector (or residual motion vector) points to the pixel unit corresponding to the MVR of the current block.

Also, in one embodiment, when adjusting the predicted motion vector and the residual motion vector considering the MVR and the minimum MVR of the current block, the motion information encoding apparatus 2700 and the motion information decoding apparatus 2500 may calculate It may be adjusted according to the following equations (2) and (2-1) instead of Equation 1-1.

&Quot; (2) &quot;

MVP '= ((MVP + offset) >> k) << k

[Mathematical Expression 2-1]

MVD '= ((MVD + offset) >> k) << k

Equation (2) and Equation (2-1) are similar to Equations (1) and (1-1), but as shown in Equations (1) and (1-1), offset is applied to a downsampled predictive motion vector and a residual motion vector It is noted that after offset is applied to the original predicted motion vector and the residual motion vector, it is downscaled according to k.

When the residual motion vector is included in the bitstream, the motion information encoding apparatus 2700 may downscale the residual motion vector as shown in Equation (3) and include information indicating the downscaled residual motion vector in the bitstream.

&Quot; (3) &quot;

MVD '= (MVD > k)

In Equation (3), MVD 'denotes a downscaled residual motion vector, k is a value determined according to the difference between the minimum MVR and the MVR of the current block, and is equal to k in Equation (1).

In one embodiment, the motion information encoding apparatus 2700 may downsample the motion vector of the current block and the adjusted predicted motion vector according to the value of k, and then may code the difference between the two values as a residual motion vector.

In one embodiment, the motion information encoding apparatus 2700 may calculate the downscaled residual motion vector according to Equation (4) instead of Equation (3).

&Quot; (4) &quot;

MVD '= (MV - PMV') / (R * S)

In Equation (4), MVD 'represents the downscaled residual motion vector, MV is the motion vector of the current block, and PMV' is the adjusted predictive motion vector. In addition, R represents a pixel unit value of the MVR of the current block, for example, 1/4 in the case of a 1/4 pixel unit MVR. In addition, S is an inverse number of the pixel unit value of the minimum MVR. When the minimum MVR is a quarter pixel unit, S represents 4.

When the MVR of the current block is greater than the minimum MVR, the motion information decoding apparatus 2500 can up-scrape the residual motion data acquired from the bitstream as shown in Equation (5) below.

&Quot; (5) &quot;

MVD '' = (MVD '<< k)

In Equation (5), MVD 'represents a downscaled residual motion vector at the encoder side, and MVD' represents an upscaled residual motion vector. K is a value determined according to the difference between the minimum MVR and the MVR of the current block, which is the same as k in Equation (1).

In one embodiment, the motion information decoding apparatus 2500 may determine an upscaled residual motion vector according to Equation (6) instead of Equation (5).

&Quot; (6) &quot;

MVD '' = MVD '* (R * S)

In Equation (6), MVD 'represents a downscaled residual motion vector, and R represents a pixel unit value of the MVR of the current block, for example, 1/4 in the case of a 1/4 pixel unit MVR. In addition, S is an inverse number of the pixel unit value of the minimum MVR. When the minimum MVR is a quarter pixel unit, S represents 4.

Meanwhile, the above-described embodiments can be made into a program that can be executed in a computer, and the created program can be stored in a medium.

The medium may be one that continues to store computer executable programs, or temporarily store them for execution or download. In addition, the medium may be a variety of recording means or storage means in the form of a combination of a single hardware or a plurality of hardware, but is not limited to a medium directly connected to a computer system, but may be dispersed on a network. Examples of the medium include a magnetic medium such as a hard disk, a floppy disk and a magnetic tape, an optical recording medium such as CD-ROM and DVD, a magneto-optical medium such as a floptical disk, And program instructions including ROM, RAM, flash memory, and the like. As another example of the medium, a recording medium or a storage medium managed by a site or a server that supplies or distributes an application store or various other software to distribute the application may be mentioned.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Various modifications and variations are possible.

Claims (15)

Identifying a type of skip motion information not included in the bitstream among a plurality of motion information used for decoding the inter-predicted current block; Obtaining the skip motion information based on a predetermined scheme; And And decoding the current block based on a plurality of pieces of motion information including the obtained skip motion information. The method according to claim 1, The skip motion information may include: The presence of the motion information is first obtained based on the motion information of the identified candidate block, while confirming the presence or absence of the motion information in accordance with the priority order for a plurality of candidate blocks spatially or temporally related to the current block Of the motion information. The method according to claim 1, The skip motion information may include: Wherein the motion information is obtained by combining motion information of a plurality of candidate blocks having motion information among a plurality of candidate blocks spatially or temporally related to the current block. The method according to claim 1, The skip motion information may include: Wherein the motion information is obtained based on predetermined basic motion information. The method according to claim 1, The skip motion information may include: Wherein the motion information is obtained based on motion information derived through DMVD (decoder side MV derivation). The method according to claim 1, Wherein the step of acquiring the skip motion information comprises: And obtaining each of the plurality of omitted motion information based on different schemes when the number of the omitted motion information is a plurality The method according to claim 1, The type of the skip motion information may be, Wherein the motion information is identified based on at least one of a motion vector resolution of the current block, a prediction direction of the current block, information on the current block, information on a previously decoded neighboring block, and information indicating an omission mode of motion information Of the motion information. The method according to claim 1, The method of decoding motion information comprises: Further comprising the step of acquiring information indicating whether or not the motion information omission process is applied, And when the application of the motion information omission process is confirmed, the type of the omission motion information is identified. 9. The method of claim 8, Information indicating whether or not the motion information skip processing is applied, And a flag indicating whether or not a skip process of the motion information is applied, based on a motion vector of the current block, a prediction direction of the current block, information on the current block, information on a previously decoded neighboring block, And decodes the motion information. The method according to claim 1, The method of decoding motion information comprises: Further comprising the step of acquiring information indicating a skip mode of the motion information when the current block is bidirectionally predicted, The skip mode of the motion information includes a first mode in which a residual motion vector corresponding to the first reference video list is identified as the skip motion information and a second mode in which a residual motion vector corresponding to the second reference video list is identified as the skip motion information And a second mode in which the motion information is decoded. The method according to claim 1, Wherein the plurality of motion information includes information indicating a motion vector resolution of a current block and information indicating a predicted motion vector, The method of decoding motion information comprises: And adjusting the predicted motion vector according to a motion vector resolution of the current block. The method according to claim 1, The method of decoding motion information comprises: Further comprising the step of acquiring motion information other than the skip motion information from the bit stream among the plurality of motion information. Obtaining information indicating a bi-directional prediction type for a current block predicted bi-directionally; And And a second residual motion vector corresponding to a second reference motion vector list corresponding to a first reference image list and a second residual motion vector corresponding to a second reference motion vector list among a plurality of pieces of motion information associated with the current block, And decoding the current block using motion information other than one motion information. An identification unit for identifying a type of skip motion information not included in the bitstream among a plurality of motion information used for decoding the inter-predicted current block; And And a decoding unit which obtains the skip motion information based on a predetermined method and decodes the current block based on a plurality of pieces of motion information including the obtained skip motion information. Determining a type of skip motion information to be skipped from the bitstream, among a plurality of motion information used for decoding the inter-predicted current block; Obtaining the skip motion information based on a predetermined scheme; And And generating a bitstream including motion information other than the skip motion information among the plurality of motion information.

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